82ba2c2ab3
General register located in LPSS SPI private register space is not found in upcoming Intel LPSS platforms. Access it conditionally depending is it defined in configuration. Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com> Signed-off-by: Mark Brown <broonie@kernel.org>
1632 lines
42 KiB
C
1632 lines
42 KiB
C
/*
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* Copyright (C) 2005 Stephen Street / StreetFire Sound Labs
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* Copyright (C) 2013, Intel Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/device.h>
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#include <linux/ioport.h>
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#include <linux/errno.h>
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#include <linux/err.h>
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#include <linux/interrupt.h>
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#include <linux/kernel.h>
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#include <linux/platform_device.h>
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#include <linux/spi/pxa2xx_spi.h>
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#include <linux/spi/spi.h>
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#include <linux/delay.h>
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#include <linux/gpio.h>
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#include <linux/slab.h>
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#include <linux/clk.h>
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#include <linux/pm_runtime.h>
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#include <linux/acpi.h>
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#include "spi-pxa2xx.h"
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MODULE_AUTHOR("Stephen Street");
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MODULE_DESCRIPTION("PXA2xx SSP SPI Controller");
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("platform:pxa2xx-spi");
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#define TIMOUT_DFLT 1000
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/*
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* for testing SSCR1 changes that require SSP restart, basically
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* everything except the service and interrupt enables, the pxa270 developer
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* manual says only SSCR1_SCFR, SSCR1_SPH, SSCR1_SPO need to be in this
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* list, but the PXA255 dev man says all bits without really meaning the
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* service and interrupt enables
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*/
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#define SSCR1_CHANGE_MASK (SSCR1_TTELP | SSCR1_TTE | SSCR1_SCFR \
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| SSCR1_ECRA | SSCR1_ECRB | SSCR1_SCLKDIR \
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| SSCR1_SFRMDIR | SSCR1_RWOT | SSCR1_TRAIL \
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| SSCR1_IFS | SSCR1_STRF | SSCR1_EFWR \
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| SSCR1_RFT | SSCR1_TFT | SSCR1_MWDS \
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| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
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#define QUARK_X1000_SSCR1_CHANGE_MASK (QUARK_X1000_SSCR1_STRF \
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| QUARK_X1000_SSCR1_EFWR \
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| QUARK_X1000_SSCR1_RFT \
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| QUARK_X1000_SSCR1_TFT \
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| SSCR1_SPH | SSCR1_SPO | SSCR1_LBM)
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#define GENERAL_REG_RXTO_HOLDOFF_DISABLE BIT(24)
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#define SPI_CS_CONTROL_SW_MODE BIT(0)
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#define SPI_CS_CONTROL_CS_HIGH BIT(1)
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struct lpss_config {
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/* LPSS offset from drv_data->ioaddr */
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unsigned offset;
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/* Register offsets from drv_data->lpss_base or -1 */
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int reg_general;
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int reg_ssp;
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int reg_cs_ctrl;
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/* FIFO thresholds */
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u32 rx_threshold;
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u32 tx_threshold_lo;
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u32 tx_threshold_hi;
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};
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/* Keep these sorted with enum pxa_ssp_type */
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static const struct lpss_config lpss_platforms[] = {
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{ /* LPSS_LPT_SSP */
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.offset = 0x800,
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.reg_general = 0x08,
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.reg_ssp = 0x0c,
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.reg_cs_ctrl = 0x18,
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.rx_threshold = 64,
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.tx_threshold_lo = 160,
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.tx_threshold_hi = 224,
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},
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{ /* LPSS_BYT_SSP */
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.offset = 0x400,
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.reg_general = 0x08,
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.reg_ssp = 0x0c,
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.reg_cs_ctrl = 0x18,
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.rx_threshold = 64,
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.tx_threshold_lo = 160,
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.tx_threshold_hi = 224,
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},
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};
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static inline const struct lpss_config
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*lpss_get_config(const struct driver_data *drv_data)
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{
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return &lpss_platforms[drv_data->ssp_type - LPSS_LPT_SSP];
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}
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static bool is_lpss_ssp(const struct driver_data *drv_data)
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{
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switch (drv_data->ssp_type) {
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case LPSS_LPT_SSP:
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case LPSS_BYT_SSP:
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return true;
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default:
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return false;
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}
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}
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static bool is_quark_x1000_ssp(const struct driver_data *drv_data)
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{
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return drv_data->ssp_type == QUARK_X1000_SSP;
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}
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static u32 pxa2xx_spi_get_ssrc1_change_mask(const struct driver_data *drv_data)
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{
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switch (drv_data->ssp_type) {
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case QUARK_X1000_SSP:
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return QUARK_X1000_SSCR1_CHANGE_MASK;
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default:
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return SSCR1_CHANGE_MASK;
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}
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}
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static u32
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pxa2xx_spi_get_rx_default_thre(const struct driver_data *drv_data)
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{
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switch (drv_data->ssp_type) {
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case QUARK_X1000_SSP:
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return RX_THRESH_QUARK_X1000_DFLT;
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default:
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return RX_THRESH_DFLT;
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}
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}
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static bool pxa2xx_spi_txfifo_full(const struct driver_data *drv_data)
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{
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u32 mask;
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switch (drv_data->ssp_type) {
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case QUARK_X1000_SSP:
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mask = QUARK_X1000_SSSR_TFL_MASK;
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break;
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default:
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mask = SSSR_TFL_MASK;
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break;
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}
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return (pxa2xx_spi_read(drv_data, SSSR) & mask) == mask;
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}
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static void pxa2xx_spi_clear_rx_thre(const struct driver_data *drv_data,
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u32 *sccr1_reg)
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{
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u32 mask;
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switch (drv_data->ssp_type) {
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case QUARK_X1000_SSP:
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mask = QUARK_X1000_SSCR1_RFT;
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break;
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default:
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mask = SSCR1_RFT;
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break;
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}
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*sccr1_reg &= ~mask;
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}
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static void pxa2xx_spi_set_rx_thre(const struct driver_data *drv_data,
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u32 *sccr1_reg, u32 threshold)
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{
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switch (drv_data->ssp_type) {
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case QUARK_X1000_SSP:
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*sccr1_reg |= QUARK_X1000_SSCR1_RxTresh(threshold);
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break;
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default:
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*sccr1_reg |= SSCR1_RxTresh(threshold);
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break;
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}
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}
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static u32 pxa2xx_configure_sscr0(const struct driver_data *drv_data,
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u32 clk_div, u8 bits)
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{
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switch (drv_data->ssp_type) {
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case QUARK_X1000_SSP:
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return clk_div
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| QUARK_X1000_SSCR0_Motorola
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| QUARK_X1000_SSCR0_DataSize(bits > 32 ? 8 : bits)
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| SSCR0_SSE;
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default:
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return clk_div
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| SSCR0_Motorola
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| SSCR0_DataSize(bits > 16 ? bits - 16 : bits)
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| SSCR0_SSE
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| (bits > 16 ? SSCR0_EDSS : 0);
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}
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}
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/*
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* Read and write LPSS SSP private registers. Caller must first check that
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* is_lpss_ssp() returns true before these can be called.
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*/
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static u32 __lpss_ssp_read_priv(struct driver_data *drv_data, unsigned offset)
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{
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WARN_ON(!drv_data->lpss_base);
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return readl(drv_data->lpss_base + offset);
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}
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static void __lpss_ssp_write_priv(struct driver_data *drv_data,
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unsigned offset, u32 value)
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{
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WARN_ON(!drv_data->lpss_base);
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writel(value, drv_data->lpss_base + offset);
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}
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/*
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* lpss_ssp_setup - perform LPSS SSP specific setup
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* @drv_data: pointer to the driver private data
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*
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* Perform LPSS SSP specific setup. This function must be called first if
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* one is going to use LPSS SSP private registers.
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*/
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static void lpss_ssp_setup(struct driver_data *drv_data)
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{
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const struct lpss_config *config;
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u32 value;
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config = lpss_get_config(drv_data);
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drv_data->lpss_base = drv_data->ioaddr + config->offset;
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/* Enable software chip select control */
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value = SPI_CS_CONTROL_SW_MODE | SPI_CS_CONTROL_CS_HIGH;
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__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
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/* Enable multiblock DMA transfers */
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if (drv_data->master_info->enable_dma) {
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__lpss_ssp_write_priv(drv_data, config->reg_ssp, 1);
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if (config->reg_general >= 0) {
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value = __lpss_ssp_read_priv(drv_data,
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config->reg_general);
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value |= GENERAL_REG_RXTO_HOLDOFF_DISABLE;
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__lpss_ssp_write_priv(drv_data,
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config->reg_general, value);
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}
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}
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}
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static void lpss_ssp_cs_control(struct driver_data *drv_data, bool enable)
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{
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const struct lpss_config *config;
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u32 value;
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config = lpss_get_config(drv_data);
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value = __lpss_ssp_read_priv(drv_data, config->reg_cs_ctrl);
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if (enable)
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value &= ~SPI_CS_CONTROL_CS_HIGH;
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else
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value |= SPI_CS_CONTROL_CS_HIGH;
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__lpss_ssp_write_priv(drv_data, config->reg_cs_ctrl, value);
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}
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static void cs_assert(struct driver_data *drv_data)
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{
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struct chip_data *chip = drv_data->cur_chip;
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if (drv_data->ssp_type == CE4100_SSP) {
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pxa2xx_spi_write(drv_data, SSSR, drv_data->cur_chip->frm);
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return;
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}
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if (chip->cs_control) {
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chip->cs_control(PXA2XX_CS_ASSERT);
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return;
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}
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if (gpio_is_valid(chip->gpio_cs)) {
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gpio_set_value(chip->gpio_cs, chip->gpio_cs_inverted);
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return;
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}
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if (is_lpss_ssp(drv_data))
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lpss_ssp_cs_control(drv_data, true);
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}
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static void cs_deassert(struct driver_data *drv_data)
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{
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struct chip_data *chip = drv_data->cur_chip;
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if (drv_data->ssp_type == CE4100_SSP)
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return;
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if (chip->cs_control) {
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chip->cs_control(PXA2XX_CS_DEASSERT);
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return;
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}
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if (gpio_is_valid(chip->gpio_cs)) {
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gpio_set_value(chip->gpio_cs, !chip->gpio_cs_inverted);
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return;
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}
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if (is_lpss_ssp(drv_data))
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lpss_ssp_cs_control(drv_data, false);
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}
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int pxa2xx_spi_flush(struct driver_data *drv_data)
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{
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unsigned long limit = loops_per_jiffy << 1;
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do {
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while (pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
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pxa2xx_spi_read(drv_data, SSDR);
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} while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_BSY) && --limit);
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write_SSSR_CS(drv_data, SSSR_ROR);
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return limit;
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}
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static int null_writer(struct driver_data *drv_data)
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{
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u8 n_bytes = drv_data->n_bytes;
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if (pxa2xx_spi_txfifo_full(drv_data)
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|| (drv_data->tx == drv_data->tx_end))
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return 0;
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pxa2xx_spi_write(drv_data, SSDR, 0);
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drv_data->tx += n_bytes;
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return 1;
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}
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static int null_reader(struct driver_data *drv_data)
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{
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u8 n_bytes = drv_data->n_bytes;
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while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
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&& (drv_data->rx < drv_data->rx_end)) {
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pxa2xx_spi_read(drv_data, SSDR);
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drv_data->rx += n_bytes;
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}
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return drv_data->rx == drv_data->rx_end;
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}
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static int u8_writer(struct driver_data *drv_data)
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{
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if (pxa2xx_spi_txfifo_full(drv_data)
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|| (drv_data->tx == drv_data->tx_end))
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return 0;
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pxa2xx_spi_write(drv_data, SSDR, *(u8 *)(drv_data->tx));
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++drv_data->tx;
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return 1;
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}
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static int u8_reader(struct driver_data *drv_data)
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{
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while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
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&& (drv_data->rx < drv_data->rx_end)) {
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*(u8 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
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++drv_data->rx;
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}
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return drv_data->rx == drv_data->rx_end;
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}
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static int u16_writer(struct driver_data *drv_data)
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{
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if (pxa2xx_spi_txfifo_full(drv_data)
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|| (drv_data->tx == drv_data->tx_end))
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return 0;
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pxa2xx_spi_write(drv_data, SSDR, *(u16 *)(drv_data->tx));
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drv_data->tx += 2;
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return 1;
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}
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static int u16_reader(struct driver_data *drv_data)
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{
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while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
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&& (drv_data->rx < drv_data->rx_end)) {
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*(u16 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
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drv_data->rx += 2;
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}
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return drv_data->rx == drv_data->rx_end;
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}
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static int u32_writer(struct driver_data *drv_data)
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{
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if (pxa2xx_spi_txfifo_full(drv_data)
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|| (drv_data->tx == drv_data->tx_end))
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return 0;
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pxa2xx_spi_write(drv_data, SSDR, *(u32 *)(drv_data->tx));
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drv_data->tx += 4;
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return 1;
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}
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static int u32_reader(struct driver_data *drv_data)
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{
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while ((pxa2xx_spi_read(drv_data, SSSR) & SSSR_RNE)
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&& (drv_data->rx < drv_data->rx_end)) {
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*(u32 *)(drv_data->rx) = pxa2xx_spi_read(drv_data, SSDR);
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drv_data->rx += 4;
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}
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return drv_data->rx == drv_data->rx_end;
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}
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void *pxa2xx_spi_next_transfer(struct driver_data *drv_data)
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{
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struct spi_message *msg = drv_data->cur_msg;
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struct spi_transfer *trans = drv_data->cur_transfer;
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/* Move to next transfer */
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if (trans->transfer_list.next != &msg->transfers) {
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drv_data->cur_transfer =
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list_entry(trans->transfer_list.next,
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struct spi_transfer,
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transfer_list);
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return RUNNING_STATE;
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} else
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return DONE_STATE;
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}
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/* caller already set message->status; dma and pio irqs are blocked */
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static void giveback(struct driver_data *drv_data)
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{
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struct spi_transfer* last_transfer;
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struct spi_message *msg;
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msg = drv_data->cur_msg;
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drv_data->cur_msg = NULL;
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drv_data->cur_transfer = NULL;
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last_transfer = list_last_entry(&msg->transfers, struct spi_transfer,
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transfer_list);
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/* Delay if requested before any change in chip select */
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if (last_transfer->delay_usecs)
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udelay(last_transfer->delay_usecs);
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/* Drop chip select UNLESS cs_change is true or we are returning
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* a message with an error, or next message is for another chip
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*/
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if (!last_transfer->cs_change)
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cs_deassert(drv_data);
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else {
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struct spi_message *next_msg;
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/* Holding of cs was hinted, but we need to make sure
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* the next message is for the same chip. Don't waste
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* time with the following tests unless this was hinted.
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*
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* We cannot postpone this until pump_messages, because
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* after calling msg->complete (below) the driver that
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* sent the current message could be unloaded, which
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* could invalidate the cs_control() callback...
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*/
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/* get a pointer to the next message, if any */
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next_msg = spi_get_next_queued_message(drv_data->master);
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/* see if the next and current messages point
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* to the same chip
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*/
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if (next_msg && next_msg->spi != msg->spi)
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next_msg = NULL;
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if (!next_msg || msg->state == ERROR_STATE)
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cs_deassert(drv_data);
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}
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drv_data->cur_chip = NULL;
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spi_finalize_current_message(drv_data->master);
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}
|
|
|
|
static void reset_sccr1(struct driver_data *drv_data)
|
|
{
|
|
struct chip_data *chip = drv_data->cur_chip;
|
|
u32 sccr1_reg;
|
|
|
|
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1) & ~drv_data->int_cr1;
|
|
sccr1_reg &= ~SSCR1_RFT;
|
|
sccr1_reg |= chip->threshold;
|
|
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
|
|
}
|
|
|
|
static void int_error_stop(struct driver_data *drv_data, const char* msg)
|
|
{
|
|
/* Stop and reset SSP */
|
|
write_SSSR_CS(drv_data, drv_data->clear_sr);
|
|
reset_sccr1(drv_data);
|
|
if (!pxa25x_ssp_comp(drv_data))
|
|
pxa2xx_spi_write(drv_data, SSTO, 0);
|
|
pxa2xx_spi_flush(drv_data);
|
|
pxa2xx_spi_write(drv_data, SSCR0,
|
|
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
|
|
|
|
dev_err(&drv_data->pdev->dev, "%s\n", msg);
|
|
|
|
drv_data->cur_msg->state = ERROR_STATE;
|
|
tasklet_schedule(&drv_data->pump_transfers);
|
|
}
|
|
|
|
static void int_transfer_complete(struct driver_data *drv_data)
|
|
{
|
|
/* Stop SSP */
|
|
write_SSSR_CS(drv_data, drv_data->clear_sr);
|
|
reset_sccr1(drv_data);
|
|
if (!pxa25x_ssp_comp(drv_data))
|
|
pxa2xx_spi_write(drv_data, SSTO, 0);
|
|
|
|
/* Update total byte transferred return count actual bytes read */
|
|
drv_data->cur_msg->actual_length += drv_data->len -
|
|
(drv_data->rx_end - drv_data->rx);
|
|
|
|
/* Transfer delays and chip select release are
|
|
* handled in pump_transfers or giveback
|
|
*/
|
|
|
|
/* Move to next transfer */
|
|
drv_data->cur_msg->state = pxa2xx_spi_next_transfer(drv_data);
|
|
|
|
/* Schedule transfer tasklet */
|
|
tasklet_schedule(&drv_data->pump_transfers);
|
|
}
|
|
|
|
static irqreturn_t interrupt_transfer(struct driver_data *drv_data)
|
|
{
|
|
u32 irq_mask = (pxa2xx_spi_read(drv_data, SSCR1) & SSCR1_TIE) ?
|
|
drv_data->mask_sr : drv_data->mask_sr & ~SSSR_TFS;
|
|
|
|
u32 irq_status = pxa2xx_spi_read(drv_data, SSSR) & irq_mask;
|
|
|
|
if (irq_status & SSSR_ROR) {
|
|
int_error_stop(drv_data, "interrupt_transfer: fifo overrun");
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
if (irq_status & SSSR_TINT) {
|
|
pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT);
|
|
if (drv_data->read(drv_data)) {
|
|
int_transfer_complete(drv_data);
|
|
return IRQ_HANDLED;
|
|
}
|
|
}
|
|
|
|
/* Drain rx fifo, Fill tx fifo and prevent overruns */
|
|
do {
|
|
if (drv_data->read(drv_data)) {
|
|
int_transfer_complete(drv_data);
|
|
return IRQ_HANDLED;
|
|
}
|
|
} while (drv_data->write(drv_data));
|
|
|
|
if (drv_data->read(drv_data)) {
|
|
int_transfer_complete(drv_data);
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
if (drv_data->tx == drv_data->tx_end) {
|
|
u32 bytes_left;
|
|
u32 sccr1_reg;
|
|
|
|
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
|
|
sccr1_reg &= ~SSCR1_TIE;
|
|
|
|
/*
|
|
* PXA25x_SSP has no timeout, set up rx threshould for the
|
|
* remaining RX bytes.
|
|
*/
|
|
if (pxa25x_ssp_comp(drv_data)) {
|
|
u32 rx_thre;
|
|
|
|
pxa2xx_spi_clear_rx_thre(drv_data, &sccr1_reg);
|
|
|
|
bytes_left = drv_data->rx_end - drv_data->rx;
|
|
switch (drv_data->n_bytes) {
|
|
case 4:
|
|
bytes_left >>= 1;
|
|
case 2:
|
|
bytes_left >>= 1;
|
|
}
|
|
|
|
rx_thre = pxa2xx_spi_get_rx_default_thre(drv_data);
|
|
if (rx_thre > bytes_left)
|
|
rx_thre = bytes_left;
|
|
|
|
pxa2xx_spi_set_rx_thre(drv_data, &sccr1_reg, rx_thre);
|
|
}
|
|
pxa2xx_spi_write(drv_data, SSCR1, sccr1_reg);
|
|
}
|
|
|
|
/* We did something */
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static irqreturn_t ssp_int(int irq, void *dev_id)
|
|
{
|
|
struct driver_data *drv_data = dev_id;
|
|
u32 sccr1_reg;
|
|
u32 mask = drv_data->mask_sr;
|
|
u32 status;
|
|
|
|
/*
|
|
* The IRQ might be shared with other peripherals so we must first
|
|
* check that are we RPM suspended or not. If we are we assume that
|
|
* the IRQ was not for us (we shouldn't be RPM suspended when the
|
|
* interrupt is enabled).
|
|
*/
|
|
if (pm_runtime_suspended(&drv_data->pdev->dev))
|
|
return IRQ_NONE;
|
|
|
|
/*
|
|
* If the device is not yet in RPM suspended state and we get an
|
|
* interrupt that is meant for another device, check if status bits
|
|
* are all set to one. That means that the device is already
|
|
* powered off.
|
|
*/
|
|
status = pxa2xx_spi_read(drv_data, SSSR);
|
|
if (status == ~0)
|
|
return IRQ_NONE;
|
|
|
|
sccr1_reg = pxa2xx_spi_read(drv_data, SSCR1);
|
|
|
|
/* Ignore possible writes if we don't need to write */
|
|
if (!(sccr1_reg & SSCR1_TIE))
|
|
mask &= ~SSSR_TFS;
|
|
|
|
if (!(status & mask))
|
|
return IRQ_NONE;
|
|
|
|
if (!drv_data->cur_msg) {
|
|
|
|
pxa2xx_spi_write(drv_data, SSCR0,
|
|
pxa2xx_spi_read(drv_data, SSCR0)
|
|
& ~SSCR0_SSE);
|
|
pxa2xx_spi_write(drv_data, SSCR1,
|
|
pxa2xx_spi_read(drv_data, SSCR1)
|
|
& ~drv_data->int_cr1);
|
|
if (!pxa25x_ssp_comp(drv_data))
|
|
pxa2xx_spi_write(drv_data, SSTO, 0);
|
|
write_SSSR_CS(drv_data, drv_data->clear_sr);
|
|
|
|
dev_err(&drv_data->pdev->dev,
|
|
"bad message state in interrupt handler\n");
|
|
|
|
/* Never fail */
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
return drv_data->transfer_handler(drv_data);
|
|
}
|
|
|
|
/*
|
|
* The Quark SPI has an additional 24 bit register (DDS_CLK_RATE) to multiply
|
|
* input frequency by fractions of 2^24. It also has a divider by 5.
|
|
*
|
|
* There are formulas to get baud rate value for given input frequency and
|
|
* divider parameters, such as DDS_CLK_RATE and SCR:
|
|
*
|
|
* Fsys = 200MHz
|
|
*
|
|
* Fssp = Fsys * DDS_CLK_RATE / 2^24 (1)
|
|
* Baud rate = Fsclk = Fssp / (2 * (SCR + 1)) (2)
|
|
*
|
|
* DDS_CLK_RATE either 2^n or 2^n / 5.
|
|
* SCR is in range 0 .. 255
|
|
*
|
|
* Divisor = 5^i * 2^j * 2 * k
|
|
* i = [0, 1] i = 1 iff j = 0 or j > 3
|
|
* j = [0, 23] j = 0 iff i = 1
|
|
* k = [1, 256]
|
|
* Special case: j = 0, i = 1: Divisor = 2 / 5
|
|
*
|
|
* Accordingly to the specification the recommended values for DDS_CLK_RATE
|
|
* are:
|
|
* Case 1: 2^n, n = [0, 23]
|
|
* Case 2: 2^24 * 2 / 5 (0x666666)
|
|
* Case 3: less than or equal to 2^24 / 5 / 16 (0x33333)
|
|
*
|
|
* In all cases the lowest possible value is better.
|
|
*
|
|
* The function calculates parameters for all cases and chooses the one closest
|
|
* to the asked baud rate.
|
|
*/
|
|
static unsigned int quark_x1000_get_clk_div(int rate, u32 *dds)
|
|
{
|
|
unsigned long xtal = 200000000;
|
|
unsigned long fref = xtal / 2; /* mandatory division by 2,
|
|
see (2) */
|
|
/* case 3 */
|
|
unsigned long fref1 = fref / 2; /* case 1 */
|
|
unsigned long fref2 = fref * 2 / 5; /* case 2 */
|
|
unsigned long scale;
|
|
unsigned long q, q1, q2;
|
|
long r, r1, r2;
|
|
u32 mul;
|
|
|
|
/* Case 1 */
|
|
|
|
/* Set initial value for DDS_CLK_RATE */
|
|
mul = (1 << 24) >> 1;
|
|
|
|
/* Calculate initial quot */
|
|
q1 = DIV_ROUND_CLOSEST(fref1, rate);
|
|
|
|
/* Scale q1 if it's too big */
|
|
if (q1 > 256) {
|
|
/* Scale q1 to range [1, 512] */
|
|
scale = fls_long(q1 - 1);
|
|
if (scale > 9) {
|
|
q1 >>= scale - 9;
|
|
mul >>= scale - 9;
|
|
}
|
|
|
|
/* Round the result if we have a remainder */
|
|
q1 += q1 & 1;
|
|
}
|
|
|
|
/* Decrease DDS_CLK_RATE as much as we can without loss in precision */
|
|
scale = __ffs(q1);
|
|
q1 >>= scale;
|
|
mul >>= scale;
|
|
|
|
/* Get the remainder */
|
|
r1 = abs(fref1 / (1 << (24 - fls_long(mul))) / q1 - rate);
|
|
|
|
/* Case 2 */
|
|
|
|
q2 = DIV_ROUND_CLOSEST(fref2, rate);
|
|
r2 = abs(fref2 / q2 - rate);
|
|
|
|
/*
|
|
* Choose the best between two: less remainder we have the better. We
|
|
* can't go case 2 if q2 is greater than 256 since SCR register can
|
|
* hold only values 0 .. 255.
|
|
*/
|
|
if (r2 >= r1 || q2 > 256) {
|
|
/* case 1 is better */
|
|
r = r1;
|
|
q = q1;
|
|
} else {
|
|
/* case 2 is better */
|
|
r = r2;
|
|
q = q2;
|
|
mul = (1 << 24) * 2 / 5;
|
|
}
|
|
|
|
/* Check case 3 only If the divisor is big enough */
|
|
if (fref / rate >= 80) {
|
|
u64 fssp;
|
|
u32 m;
|
|
|
|
/* Calculate initial quot */
|
|
q1 = DIV_ROUND_CLOSEST(fref, rate);
|
|
m = (1 << 24) / q1;
|
|
|
|
/* Get the remainder */
|
|
fssp = (u64)fref * m;
|
|
do_div(fssp, 1 << 24);
|
|
r1 = abs(fssp - rate);
|
|
|
|
/* Choose this one if it suits better */
|
|
if (r1 < r) {
|
|
/* case 3 is better */
|
|
q = 1;
|
|
mul = m;
|
|
}
|
|
}
|
|
|
|
*dds = mul;
|
|
return q - 1;
|
|
}
|
|
|
|
static unsigned int ssp_get_clk_div(struct driver_data *drv_data, int rate)
|
|
{
|
|
unsigned long ssp_clk = drv_data->max_clk_rate;
|
|
const struct ssp_device *ssp = drv_data->ssp;
|
|
|
|
rate = min_t(int, ssp_clk, rate);
|
|
|
|
if (ssp->type == PXA25x_SSP || ssp->type == CE4100_SSP)
|
|
return (ssp_clk / (2 * rate) - 1) & 0xff;
|
|
else
|
|
return (ssp_clk / rate - 1) & 0xfff;
|
|
}
|
|
|
|
static unsigned int pxa2xx_ssp_get_clk_div(struct driver_data *drv_data,
|
|
struct chip_data *chip, int rate)
|
|
{
|
|
unsigned int clk_div;
|
|
|
|
switch (drv_data->ssp_type) {
|
|
case QUARK_X1000_SSP:
|
|
clk_div = quark_x1000_get_clk_div(rate, &chip->dds_rate);
|
|
break;
|
|
default:
|
|
clk_div = ssp_get_clk_div(drv_data, rate);
|
|
break;
|
|
}
|
|
return clk_div << 8;
|
|
}
|
|
|
|
static void pump_transfers(unsigned long data)
|
|
{
|
|
struct driver_data *drv_data = (struct driver_data *)data;
|
|
struct spi_message *message = NULL;
|
|
struct spi_transfer *transfer = NULL;
|
|
struct spi_transfer *previous = NULL;
|
|
struct chip_data *chip = NULL;
|
|
u32 clk_div = 0;
|
|
u8 bits = 0;
|
|
u32 speed = 0;
|
|
u32 cr0;
|
|
u32 cr1;
|
|
u32 dma_thresh = drv_data->cur_chip->dma_threshold;
|
|
u32 dma_burst = drv_data->cur_chip->dma_burst_size;
|
|
u32 change_mask = pxa2xx_spi_get_ssrc1_change_mask(drv_data);
|
|
|
|
/* Get current state information */
|
|
message = drv_data->cur_msg;
|
|
transfer = drv_data->cur_transfer;
|
|
chip = drv_data->cur_chip;
|
|
|
|
/* Handle for abort */
|
|
if (message->state == ERROR_STATE) {
|
|
message->status = -EIO;
|
|
giveback(drv_data);
|
|
return;
|
|
}
|
|
|
|
/* Handle end of message */
|
|
if (message->state == DONE_STATE) {
|
|
message->status = 0;
|
|
giveback(drv_data);
|
|
return;
|
|
}
|
|
|
|
/* Delay if requested at end of transfer before CS change */
|
|
if (message->state == RUNNING_STATE) {
|
|
previous = list_entry(transfer->transfer_list.prev,
|
|
struct spi_transfer,
|
|
transfer_list);
|
|
if (previous->delay_usecs)
|
|
udelay(previous->delay_usecs);
|
|
|
|
/* Drop chip select only if cs_change is requested */
|
|
if (previous->cs_change)
|
|
cs_deassert(drv_data);
|
|
}
|
|
|
|
/* Check if we can DMA this transfer */
|
|
if (!pxa2xx_spi_dma_is_possible(transfer->len) && chip->enable_dma) {
|
|
|
|
/* reject already-mapped transfers; PIO won't always work */
|
|
if (message->is_dma_mapped
|
|
|| transfer->rx_dma || transfer->tx_dma) {
|
|
dev_err(&drv_data->pdev->dev,
|
|
"pump_transfers: mapped transfer length of "
|
|
"%u is greater than %d\n",
|
|
transfer->len, MAX_DMA_LEN);
|
|
message->status = -EINVAL;
|
|
giveback(drv_data);
|
|
return;
|
|
}
|
|
|
|
/* warn ... we force this to PIO mode */
|
|
dev_warn_ratelimited(&message->spi->dev,
|
|
"pump_transfers: DMA disabled for transfer length %ld "
|
|
"greater than %d\n",
|
|
(long)drv_data->len, MAX_DMA_LEN);
|
|
}
|
|
|
|
/* Setup the transfer state based on the type of transfer */
|
|
if (pxa2xx_spi_flush(drv_data) == 0) {
|
|
dev_err(&drv_data->pdev->dev, "pump_transfers: flush failed\n");
|
|
message->status = -EIO;
|
|
giveback(drv_data);
|
|
return;
|
|
}
|
|
drv_data->n_bytes = chip->n_bytes;
|
|
drv_data->tx = (void *)transfer->tx_buf;
|
|
drv_data->tx_end = drv_data->tx + transfer->len;
|
|
drv_data->rx = transfer->rx_buf;
|
|
drv_data->rx_end = drv_data->rx + transfer->len;
|
|
drv_data->rx_dma = transfer->rx_dma;
|
|
drv_data->tx_dma = transfer->tx_dma;
|
|
drv_data->len = transfer->len;
|
|
drv_data->write = drv_data->tx ? chip->write : null_writer;
|
|
drv_data->read = drv_data->rx ? chip->read : null_reader;
|
|
|
|
/* Change speed and bit per word on a per transfer */
|
|
cr0 = chip->cr0;
|
|
if (transfer->speed_hz || transfer->bits_per_word) {
|
|
|
|
bits = chip->bits_per_word;
|
|
speed = chip->speed_hz;
|
|
|
|
if (transfer->speed_hz)
|
|
speed = transfer->speed_hz;
|
|
|
|
if (transfer->bits_per_word)
|
|
bits = transfer->bits_per_word;
|
|
|
|
clk_div = pxa2xx_ssp_get_clk_div(drv_data, chip, speed);
|
|
|
|
if (bits <= 8) {
|
|
drv_data->n_bytes = 1;
|
|
drv_data->read = drv_data->read != null_reader ?
|
|
u8_reader : null_reader;
|
|
drv_data->write = drv_data->write != null_writer ?
|
|
u8_writer : null_writer;
|
|
} else if (bits <= 16) {
|
|
drv_data->n_bytes = 2;
|
|
drv_data->read = drv_data->read != null_reader ?
|
|
u16_reader : null_reader;
|
|
drv_data->write = drv_data->write != null_writer ?
|
|
u16_writer : null_writer;
|
|
} else if (bits <= 32) {
|
|
drv_data->n_bytes = 4;
|
|
drv_data->read = drv_data->read != null_reader ?
|
|
u32_reader : null_reader;
|
|
drv_data->write = drv_data->write != null_writer ?
|
|
u32_writer : null_writer;
|
|
}
|
|
/* if bits/word is changed in dma mode, then must check the
|
|
* thresholds and burst also */
|
|
if (chip->enable_dma) {
|
|
if (pxa2xx_spi_set_dma_burst_and_threshold(chip,
|
|
message->spi,
|
|
bits, &dma_burst,
|
|
&dma_thresh))
|
|
dev_warn_ratelimited(&message->spi->dev,
|
|
"pump_transfers: DMA burst size reduced to match bits_per_word\n");
|
|
}
|
|
|
|
cr0 = pxa2xx_configure_sscr0(drv_data, clk_div, bits);
|
|
}
|
|
|
|
message->state = RUNNING_STATE;
|
|
|
|
drv_data->dma_mapped = 0;
|
|
if (pxa2xx_spi_dma_is_possible(drv_data->len))
|
|
drv_data->dma_mapped = pxa2xx_spi_map_dma_buffers(drv_data);
|
|
if (drv_data->dma_mapped) {
|
|
|
|
/* Ensure we have the correct interrupt handler */
|
|
drv_data->transfer_handler = pxa2xx_spi_dma_transfer;
|
|
|
|
pxa2xx_spi_dma_prepare(drv_data, dma_burst);
|
|
|
|
/* Clear status and start DMA engine */
|
|
cr1 = chip->cr1 | dma_thresh | drv_data->dma_cr1;
|
|
pxa2xx_spi_write(drv_data, SSSR, drv_data->clear_sr);
|
|
|
|
pxa2xx_spi_dma_start(drv_data);
|
|
} else {
|
|
/* Ensure we have the correct interrupt handler */
|
|
drv_data->transfer_handler = interrupt_transfer;
|
|
|
|
/* Clear status */
|
|
cr1 = chip->cr1 | chip->threshold | drv_data->int_cr1;
|
|
write_SSSR_CS(drv_data, drv_data->clear_sr);
|
|
}
|
|
|
|
if (is_lpss_ssp(drv_data)) {
|
|
if ((pxa2xx_spi_read(drv_data, SSIRF) & 0xff)
|
|
!= chip->lpss_rx_threshold)
|
|
pxa2xx_spi_write(drv_data, SSIRF,
|
|
chip->lpss_rx_threshold);
|
|
if ((pxa2xx_spi_read(drv_data, SSITF) & 0xffff)
|
|
!= chip->lpss_tx_threshold)
|
|
pxa2xx_spi_write(drv_data, SSITF,
|
|
chip->lpss_tx_threshold);
|
|
}
|
|
|
|
if (is_quark_x1000_ssp(drv_data) &&
|
|
(pxa2xx_spi_read(drv_data, DDS_RATE) != chip->dds_rate))
|
|
pxa2xx_spi_write(drv_data, DDS_RATE, chip->dds_rate);
|
|
|
|
/* see if we need to reload the config registers */
|
|
if ((pxa2xx_spi_read(drv_data, SSCR0) != cr0)
|
|
|| (pxa2xx_spi_read(drv_data, SSCR1) & change_mask)
|
|
!= (cr1 & change_mask)) {
|
|
/* stop the SSP, and update the other bits */
|
|
pxa2xx_spi_write(drv_data, SSCR0, cr0 & ~SSCR0_SSE);
|
|
if (!pxa25x_ssp_comp(drv_data))
|
|
pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
|
|
/* first set CR1 without interrupt and service enables */
|
|
pxa2xx_spi_write(drv_data, SSCR1, cr1 & change_mask);
|
|
/* restart the SSP */
|
|
pxa2xx_spi_write(drv_data, SSCR0, cr0);
|
|
|
|
} else {
|
|
if (!pxa25x_ssp_comp(drv_data))
|
|
pxa2xx_spi_write(drv_data, SSTO, chip->timeout);
|
|
}
|
|
|
|
cs_assert(drv_data);
|
|
|
|
/* after chip select, release the data by enabling service
|
|
* requests and interrupts, without changing any mode bits */
|
|
pxa2xx_spi_write(drv_data, SSCR1, cr1);
|
|
}
|
|
|
|
static int pxa2xx_spi_transfer_one_message(struct spi_master *master,
|
|
struct spi_message *msg)
|
|
{
|
|
struct driver_data *drv_data = spi_master_get_devdata(master);
|
|
|
|
drv_data->cur_msg = msg;
|
|
/* Initial message state*/
|
|
drv_data->cur_msg->state = START_STATE;
|
|
drv_data->cur_transfer = list_entry(drv_data->cur_msg->transfers.next,
|
|
struct spi_transfer,
|
|
transfer_list);
|
|
|
|
/* prepare to setup the SSP, in pump_transfers, using the per
|
|
* chip configuration */
|
|
drv_data->cur_chip = spi_get_ctldata(drv_data->cur_msg->spi);
|
|
|
|
/* Mark as busy and launch transfers */
|
|
tasklet_schedule(&drv_data->pump_transfers);
|
|
return 0;
|
|
}
|
|
|
|
static int pxa2xx_spi_unprepare_transfer(struct spi_master *master)
|
|
{
|
|
struct driver_data *drv_data = spi_master_get_devdata(master);
|
|
|
|
/* Disable the SSP now */
|
|
pxa2xx_spi_write(drv_data, SSCR0,
|
|
pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int setup_cs(struct spi_device *spi, struct chip_data *chip,
|
|
struct pxa2xx_spi_chip *chip_info)
|
|
{
|
|
int err = 0;
|
|
|
|
if (chip == NULL || chip_info == NULL)
|
|
return 0;
|
|
|
|
/* NOTE: setup() can be called multiple times, possibly with
|
|
* different chip_info, release previously requested GPIO
|
|
*/
|
|
if (gpio_is_valid(chip->gpio_cs))
|
|
gpio_free(chip->gpio_cs);
|
|
|
|
/* If (*cs_control) is provided, ignore GPIO chip select */
|
|
if (chip_info->cs_control) {
|
|
chip->cs_control = chip_info->cs_control;
|
|
return 0;
|
|
}
|
|
|
|
if (gpio_is_valid(chip_info->gpio_cs)) {
|
|
err = gpio_request(chip_info->gpio_cs, "SPI_CS");
|
|
if (err) {
|
|
dev_err(&spi->dev, "failed to request chip select GPIO%d\n",
|
|
chip_info->gpio_cs);
|
|
return err;
|
|
}
|
|
|
|
chip->gpio_cs = chip_info->gpio_cs;
|
|
chip->gpio_cs_inverted = spi->mode & SPI_CS_HIGH;
|
|
|
|
err = gpio_direction_output(chip->gpio_cs,
|
|
!chip->gpio_cs_inverted);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
static int setup(struct spi_device *spi)
|
|
{
|
|
struct pxa2xx_spi_chip *chip_info = NULL;
|
|
struct chip_data *chip;
|
|
const struct lpss_config *config;
|
|
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
|
|
unsigned int clk_div;
|
|
uint tx_thres, tx_hi_thres, rx_thres;
|
|
|
|
switch (drv_data->ssp_type) {
|
|
case QUARK_X1000_SSP:
|
|
tx_thres = TX_THRESH_QUARK_X1000_DFLT;
|
|
tx_hi_thres = 0;
|
|
rx_thres = RX_THRESH_QUARK_X1000_DFLT;
|
|
break;
|
|
case LPSS_LPT_SSP:
|
|
case LPSS_BYT_SSP:
|
|
config = lpss_get_config(drv_data);
|
|
tx_thres = config->tx_threshold_lo;
|
|
tx_hi_thres = config->tx_threshold_hi;
|
|
rx_thres = config->rx_threshold;
|
|
break;
|
|
default:
|
|
tx_thres = TX_THRESH_DFLT;
|
|
tx_hi_thres = 0;
|
|
rx_thres = RX_THRESH_DFLT;
|
|
break;
|
|
}
|
|
|
|
/* Only alloc on first setup */
|
|
chip = spi_get_ctldata(spi);
|
|
if (!chip) {
|
|
chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
|
|
if (!chip)
|
|
return -ENOMEM;
|
|
|
|
if (drv_data->ssp_type == CE4100_SSP) {
|
|
if (spi->chip_select > 4) {
|
|
dev_err(&spi->dev,
|
|
"failed setup: cs number must not be > 4.\n");
|
|
kfree(chip);
|
|
return -EINVAL;
|
|
}
|
|
|
|
chip->frm = spi->chip_select;
|
|
} else
|
|
chip->gpio_cs = -1;
|
|
chip->enable_dma = 0;
|
|
chip->timeout = TIMOUT_DFLT;
|
|
}
|
|
|
|
/* protocol drivers may change the chip settings, so...
|
|
* if chip_info exists, use it */
|
|
chip_info = spi->controller_data;
|
|
|
|
/* chip_info isn't always needed */
|
|
chip->cr1 = 0;
|
|
if (chip_info) {
|
|
if (chip_info->timeout)
|
|
chip->timeout = chip_info->timeout;
|
|
if (chip_info->tx_threshold)
|
|
tx_thres = chip_info->tx_threshold;
|
|
if (chip_info->tx_hi_threshold)
|
|
tx_hi_thres = chip_info->tx_hi_threshold;
|
|
if (chip_info->rx_threshold)
|
|
rx_thres = chip_info->rx_threshold;
|
|
chip->enable_dma = drv_data->master_info->enable_dma;
|
|
chip->dma_threshold = 0;
|
|
if (chip_info->enable_loopback)
|
|
chip->cr1 = SSCR1_LBM;
|
|
} else if (ACPI_HANDLE(&spi->dev)) {
|
|
/*
|
|
* Slave devices enumerated from ACPI namespace don't
|
|
* usually have chip_info but we still might want to use
|
|
* DMA with them.
|
|
*/
|
|
chip->enable_dma = drv_data->master_info->enable_dma;
|
|
}
|
|
|
|
chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres);
|
|
chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres)
|
|
| SSITF_TxHiThresh(tx_hi_thres);
|
|
|
|
/* set dma burst and threshold outside of chip_info path so that if
|
|
* chip_info goes away after setting chip->enable_dma, the
|
|
* burst and threshold can still respond to changes in bits_per_word */
|
|
if (chip->enable_dma) {
|
|
/* set up legal burst and threshold for dma */
|
|
if (pxa2xx_spi_set_dma_burst_and_threshold(chip, spi,
|
|
spi->bits_per_word,
|
|
&chip->dma_burst_size,
|
|
&chip->dma_threshold)) {
|
|
dev_warn(&spi->dev,
|
|
"in setup: DMA burst size reduced to match bits_per_word\n");
|
|
}
|
|
}
|
|
|
|
clk_div = pxa2xx_ssp_get_clk_div(drv_data, chip, spi->max_speed_hz);
|
|
chip->speed_hz = spi->max_speed_hz;
|
|
|
|
chip->cr0 = pxa2xx_configure_sscr0(drv_data, clk_div,
|
|
spi->bits_per_word);
|
|
switch (drv_data->ssp_type) {
|
|
case QUARK_X1000_SSP:
|
|
chip->threshold = (QUARK_X1000_SSCR1_RxTresh(rx_thres)
|
|
& QUARK_X1000_SSCR1_RFT)
|
|
| (QUARK_X1000_SSCR1_TxTresh(tx_thres)
|
|
& QUARK_X1000_SSCR1_TFT);
|
|
break;
|
|
default:
|
|
chip->threshold = (SSCR1_RxTresh(rx_thres) & SSCR1_RFT) |
|
|
(SSCR1_TxTresh(tx_thres) & SSCR1_TFT);
|
|
break;
|
|
}
|
|
|
|
chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH);
|
|
chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0)
|
|
| (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0);
|
|
|
|
if (spi->mode & SPI_LOOP)
|
|
chip->cr1 |= SSCR1_LBM;
|
|
|
|
/* NOTE: PXA25x_SSP _could_ use external clocking ... */
|
|
if (!pxa25x_ssp_comp(drv_data))
|
|
dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
|
|
drv_data->max_clk_rate
|
|
/ (1 + ((chip->cr0 & SSCR0_SCR(0xfff)) >> 8)),
|
|
chip->enable_dma ? "DMA" : "PIO");
|
|
else
|
|
dev_dbg(&spi->dev, "%ld Hz actual, %s\n",
|
|
drv_data->max_clk_rate / 2
|
|
/ (1 + ((chip->cr0 & SSCR0_SCR(0x0ff)) >> 8)),
|
|
chip->enable_dma ? "DMA" : "PIO");
|
|
|
|
if (spi->bits_per_word <= 8) {
|
|
chip->n_bytes = 1;
|
|
chip->read = u8_reader;
|
|
chip->write = u8_writer;
|
|
} else if (spi->bits_per_word <= 16) {
|
|
chip->n_bytes = 2;
|
|
chip->read = u16_reader;
|
|
chip->write = u16_writer;
|
|
} else if (spi->bits_per_word <= 32) {
|
|
if (!is_quark_x1000_ssp(drv_data))
|
|
chip->cr0 |= SSCR0_EDSS;
|
|
chip->n_bytes = 4;
|
|
chip->read = u32_reader;
|
|
chip->write = u32_writer;
|
|
}
|
|
chip->bits_per_word = spi->bits_per_word;
|
|
|
|
spi_set_ctldata(spi, chip);
|
|
|
|
if (drv_data->ssp_type == CE4100_SSP)
|
|
return 0;
|
|
|
|
return setup_cs(spi, chip, chip_info);
|
|
}
|
|
|
|
static void cleanup(struct spi_device *spi)
|
|
{
|
|
struct chip_data *chip = spi_get_ctldata(spi);
|
|
struct driver_data *drv_data = spi_master_get_devdata(spi->master);
|
|
|
|
if (!chip)
|
|
return;
|
|
|
|
if (drv_data->ssp_type != CE4100_SSP && gpio_is_valid(chip->gpio_cs))
|
|
gpio_free(chip->gpio_cs);
|
|
|
|
kfree(chip);
|
|
}
|
|
|
|
#ifdef CONFIG_ACPI
|
|
|
|
static struct acpi_device_id pxa2xx_spi_acpi_match[] = {
|
|
{ "INT33C0", LPSS_LPT_SSP },
|
|
{ "INT33C1", LPSS_LPT_SSP },
|
|
{ "INT3430", LPSS_LPT_SSP },
|
|
{ "INT3431", LPSS_LPT_SSP },
|
|
{ "80860F0E", LPSS_BYT_SSP },
|
|
{ "8086228E", LPSS_BYT_SSP },
|
|
{ },
|
|
};
|
|
MODULE_DEVICE_TABLE(acpi, pxa2xx_spi_acpi_match);
|
|
|
|
static struct pxa2xx_spi_master *
|
|
pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
|
|
{
|
|
struct pxa2xx_spi_master *pdata;
|
|
struct acpi_device *adev;
|
|
struct ssp_device *ssp;
|
|
struct resource *res;
|
|
const struct acpi_device_id *id;
|
|
int devid, type;
|
|
|
|
if (!ACPI_HANDLE(&pdev->dev) ||
|
|
acpi_bus_get_device(ACPI_HANDLE(&pdev->dev), &adev))
|
|
return NULL;
|
|
|
|
id = acpi_match_device(pdev->dev.driver->acpi_match_table, &pdev->dev);
|
|
if (id)
|
|
type = (int)id->driver_data;
|
|
else
|
|
return NULL;
|
|
|
|
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
|
|
if (!pdata)
|
|
return NULL;
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
if (!res)
|
|
return NULL;
|
|
|
|
ssp = &pdata->ssp;
|
|
|
|
ssp->phys_base = res->start;
|
|
ssp->mmio_base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(ssp->mmio_base))
|
|
return NULL;
|
|
|
|
ssp->clk = devm_clk_get(&pdev->dev, NULL);
|
|
ssp->irq = platform_get_irq(pdev, 0);
|
|
ssp->type = type;
|
|
ssp->pdev = pdev;
|
|
|
|
ssp->port_id = -1;
|
|
if (adev->pnp.unique_id && !kstrtoint(adev->pnp.unique_id, 0, &devid))
|
|
ssp->port_id = devid;
|
|
|
|
pdata->num_chipselect = 1;
|
|
pdata->enable_dma = true;
|
|
|
|
return pdata;
|
|
}
|
|
|
|
#else
|
|
static inline struct pxa2xx_spi_master *
|
|
pxa2xx_spi_acpi_get_pdata(struct platform_device *pdev)
|
|
{
|
|
return NULL;
|
|
}
|
|
#endif
|
|
|
|
static int pxa2xx_spi_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct pxa2xx_spi_master *platform_info;
|
|
struct spi_master *master;
|
|
struct driver_data *drv_data;
|
|
struct ssp_device *ssp;
|
|
int status;
|
|
u32 tmp;
|
|
|
|
platform_info = dev_get_platdata(dev);
|
|
if (!platform_info) {
|
|
platform_info = pxa2xx_spi_acpi_get_pdata(pdev);
|
|
if (!platform_info) {
|
|
dev_err(&pdev->dev, "missing platform data\n");
|
|
return -ENODEV;
|
|
}
|
|
}
|
|
|
|
ssp = pxa_ssp_request(pdev->id, pdev->name);
|
|
if (!ssp)
|
|
ssp = &platform_info->ssp;
|
|
|
|
if (!ssp->mmio_base) {
|
|
dev_err(&pdev->dev, "failed to get ssp\n");
|
|
return -ENODEV;
|
|
}
|
|
|
|
/* Allocate master with space for drv_data and null dma buffer */
|
|
master = spi_alloc_master(dev, sizeof(struct driver_data) + 16);
|
|
if (!master) {
|
|
dev_err(&pdev->dev, "cannot alloc spi_master\n");
|
|
pxa_ssp_free(ssp);
|
|
return -ENOMEM;
|
|
}
|
|
drv_data = spi_master_get_devdata(master);
|
|
drv_data->master = master;
|
|
drv_data->master_info = platform_info;
|
|
drv_data->pdev = pdev;
|
|
drv_data->ssp = ssp;
|
|
|
|
master->dev.parent = &pdev->dev;
|
|
master->dev.of_node = pdev->dev.of_node;
|
|
/* the spi->mode bits understood by this driver: */
|
|
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_LOOP;
|
|
|
|
master->bus_num = ssp->port_id;
|
|
master->num_chipselect = platform_info->num_chipselect;
|
|
master->dma_alignment = DMA_ALIGNMENT;
|
|
master->cleanup = cleanup;
|
|
master->setup = setup;
|
|
master->transfer_one_message = pxa2xx_spi_transfer_one_message;
|
|
master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer;
|
|
master->auto_runtime_pm = true;
|
|
|
|
drv_data->ssp_type = ssp->type;
|
|
drv_data->null_dma_buf = (u32 *)PTR_ALIGN(&drv_data[1], DMA_ALIGNMENT);
|
|
|
|
drv_data->ioaddr = ssp->mmio_base;
|
|
drv_data->ssdr_physical = ssp->phys_base + SSDR;
|
|
if (pxa25x_ssp_comp(drv_data)) {
|
|
switch (drv_data->ssp_type) {
|
|
case QUARK_X1000_SSP:
|
|
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
|
|
break;
|
|
default:
|
|
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 16);
|
|
break;
|
|
}
|
|
|
|
drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE;
|
|
drv_data->dma_cr1 = 0;
|
|
drv_data->clear_sr = SSSR_ROR;
|
|
drv_data->mask_sr = SSSR_RFS | SSSR_TFS | SSSR_ROR;
|
|
} else {
|
|
master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32);
|
|
drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE;
|
|
drv_data->dma_cr1 = DEFAULT_DMA_CR1;
|
|
drv_data->clear_sr = SSSR_ROR | SSSR_TINT;
|
|
drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR;
|
|
}
|
|
|
|
status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev),
|
|
drv_data);
|
|
if (status < 0) {
|
|
dev_err(&pdev->dev, "cannot get IRQ %d\n", ssp->irq);
|
|
goto out_error_master_alloc;
|
|
}
|
|
|
|
/* Setup DMA if requested */
|
|
drv_data->tx_channel = -1;
|
|
drv_data->rx_channel = -1;
|
|
if (platform_info->enable_dma) {
|
|
status = pxa2xx_spi_dma_setup(drv_data);
|
|
if (status) {
|
|
dev_dbg(dev, "no DMA channels available, using PIO\n");
|
|
platform_info->enable_dma = false;
|
|
}
|
|
}
|
|
|
|
/* Enable SOC clock */
|
|
clk_prepare_enable(ssp->clk);
|
|
|
|
drv_data->max_clk_rate = clk_get_rate(ssp->clk);
|
|
|
|
/* Load default SSP configuration */
|
|
pxa2xx_spi_write(drv_data, SSCR0, 0);
|
|
switch (drv_data->ssp_type) {
|
|
case QUARK_X1000_SSP:
|
|
tmp = QUARK_X1000_SSCR1_RxTresh(RX_THRESH_QUARK_X1000_DFLT)
|
|
| QUARK_X1000_SSCR1_TxTresh(TX_THRESH_QUARK_X1000_DFLT);
|
|
pxa2xx_spi_write(drv_data, SSCR1, tmp);
|
|
|
|
/* using the Motorola SPI protocol and use 8 bit frame */
|
|
pxa2xx_spi_write(drv_data, SSCR0,
|
|
QUARK_X1000_SSCR0_Motorola
|
|
| QUARK_X1000_SSCR0_DataSize(8));
|
|
break;
|
|
default:
|
|
tmp = SSCR1_RxTresh(RX_THRESH_DFLT) |
|
|
SSCR1_TxTresh(TX_THRESH_DFLT);
|
|
pxa2xx_spi_write(drv_data, SSCR1, tmp);
|
|
tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8);
|
|
pxa2xx_spi_write(drv_data, SSCR0, tmp);
|
|
break;
|
|
}
|
|
|
|
if (!pxa25x_ssp_comp(drv_data))
|
|
pxa2xx_spi_write(drv_data, SSTO, 0);
|
|
|
|
if (!is_quark_x1000_ssp(drv_data))
|
|
pxa2xx_spi_write(drv_data, SSPSP, 0);
|
|
|
|
if (is_lpss_ssp(drv_data))
|
|
lpss_ssp_setup(drv_data);
|
|
|
|
tasklet_init(&drv_data->pump_transfers, pump_transfers,
|
|
(unsigned long)drv_data);
|
|
|
|
pm_runtime_set_autosuspend_delay(&pdev->dev, 50);
|
|
pm_runtime_use_autosuspend(&pdev->dev);
|
|
pm_runtime_set_active(&pdev->dev);
|
|
pm_runtime_enable(&pdev->dev);
|
|
|
|
/* Register with the SPI framework */
|
|
platform_set_drvdata(pdev, drv_data);
|
|
status = devm_spi_register_master(&pdev->dev, master);
|
|
if (status != 0) {
|
|
dev_err(&pdev->dev, "problem registering spi master\n");
|
|
goto out_error_clock_enabled;
|
|
}
|
|
|
|
return status;
|
|
|
|
out_error_clock_enabled:
|
|
clk_disable_unprepare(ssp->clk);
|
|
pxa2xx_spi_dma_release(drv_data);
|
|
free_irq(ssp->irq, drv_data);
|
|
|
|
out_error_master_alloc:
|
|
spi_master_put(master);
|
|
pxa_ssp_free(ssp);
|
|
return status;
|
|
}
|
|
|
|
static int pxa2xx_spi_remove(struct platform_device *pdev)
|
|
{
|
|
struct driver_data *drv_data = platform_get_drvdata(pdev);
|
|
struct ssp_device *ssp;
|
|
|
|
if (!drv_data)
|
|
return 0;
|
|
ssp = drv_data->ssp;
|
|
|
|
pm_runtime_get_sync(&pdev->dev);
|
|
|
|
/* Disable the SSP at the peripheral and SOC level */
|
|
pxa2xx_spi_write(drv_data, SSCR0, 0);
|
|
clk_disable_unprepare(ssp->clk);
|
|
|
|
/* Release DMA */
|
|
if (drv_data->master_info->enable_dma)
|
|
pxa2xx_spi_dma_release(drv_data);
|
|
|
|
pm_runtime_put_noidle(&pdev->dev);
|
|
pm_runtime_disable(&pdev->dev);
|
|
|
|
/* Release IRQ */
|
|
free_irq(ssp->irq, drv_data);
|
|
|
|
/* Release SSP */
|
|
pxa_ssp_free(ssp);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void pxa2xx_spi_shutdown(struct platform_device *pdev)
|
|
{
|
|
int status = 0;
|
|
|
|
if ((status = pxa2xx_spi_remove(pdev)) != 0)
|
|
dev_err(&pdev->dev, "shutdown failed with %d\n", status);
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int pxa2xx_spi_suspend(struct device *dev)
|
|
{
|
|
struct driver_data *drv_data = dev_get_drvdata(dev);
|
|
struct ssp_device *ssp = drv_data->ssp;
|
|
int status = 0;
|
|
|
|
status = spi_master_suspend(drv_data->master);
|
|
if (status != 0)
|
|
return status;
|
|
pxa2xx_spi_write(drv_data, SSCR0, 0);
|
|
|
|
if (!pm_runtime_suspended(dev))
|
|
clk_disable_unprepare(ssp->clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int pxa2xx_spi_resume(struct device *dev)
|
|
{
|
|
struct driver_data *drv_data = dev_get_drvdata(dev);
|
|
struct ssp_device *ssp = drv_data->ssp;
|
|
int status = 0;
|
|
|
|
pxa2xx_spi_dma_resume(drv_data);
|
|
|
|
/* Enable the SSP clock */
|
|
if (!pm_runtime_suspended(dev))
|
|
clk_prepare_enable(ssp->clk);
|
|
|
|
/* Restore LPSS private register bits */
|
|
if (is_lpss_ssp(drv_data))
|
|
lpss_ssp_setup(drv_data);
|
|
|
|
/* Start the queue running */
|
|
status = spi_master_resume(drv_data->master);
|
|
if (status != 0) {
|
|
dev_err(dev, "problem starting queue (%d)\n", status);
|
|
return status;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_PM
|
|
static int pxa2xx_spi_runtime_suspend(struct device *dev)
|
|
{
|
|
struct driver_data *drv_data = dev_get_drvdata(dev);
|
|
|
|
clk_disable_unprepare(drv_data->ssp->clk);
|
|
return 0;
|
|
}
|
|
|
|
static int pxa2xx_spi_runtime_resume(struct device *dev)
|
|
{
|
|
struct driver_data *drv_data = dev_get_drvdata(dev);
|
|
|
|
clk_prepare_enable(drv_data->ssp->clk);
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static const struct dev_pm_ops pxa2xx_spi_pm_ops = {
|
|
SET_SYSTEM_SLEEP_PM_OPS(pxa2xx_spi_suspend, pxa2xx_spi_resume)
|
|
SET_RUNTIME_PM_OPS(pxa2xx_spi_runtime_suspend,
|
|
pxa2xx_spi_runtime_resume, NULL)
|
|
};
|
|
|
|
static struct platform_driver driver = {
|
|
.driver = {
|
|
.name = "pxa2xx-spi",
|
|
.pm = &pxa2xx_spi_pm_ops,
|
|
.acpi_match_table = ACPI_PTR(pxa2xx_spi_acpi_match),
|
|
},
|
|
.probe = pxa2xx_spi_probe,
|
|
.remove = pxa2xx_spi_remove,
|
|
.shutdown = pxa2xx_spi_shutdown,
|
|
};
|
|
|
|
static int __init pxa2xx_spi_init(void)
|
|
{
|
|
return platform_driver_register(&driver);
|
|
}
|
|
subsys_initcall(pxa2xx_spi_init);
|
|
|
|
static void __exit pxa2xx_spi_exit(void)
|
|
{
|
|
platform_driver_unregister(&driver);
|
|
}
|
|
module_exit(pxa2xx_spi_exit);
|