forked from luck/tmp_suning_uos_patched
bf51a8c5e0
i2c_del_adapter() always returns 0. So all checks testing whether it will be non zero will always evaluate to false and the conditional code is dead code. This patch updates all callers of i2c_del_mux_adapter() to ignore the return value and assume that it will always succeed (which it will). In a subsequent patch the return type of i2c_del_adapter() will be made void. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Acked-by: Ben Hutchings <bhutchings@solarflare.com> Reviewed-by: Jean Delvare <khali@linux-fr.org> Acked-by: Shawn Guo <shawn.guo@linaro.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
741 lines
20 KiB
C
741 lines
20 KiB
C
/*
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* Driver for the i2c controller on the Marvell line of host bridges
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* (e.g, gt642[46]0, mv643[46]0, mv644[46]0, and Orion SoC family).
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*
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* Author: Mark A. Greer <mgreer@mvista.com>
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*
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* 2005 (c) MontaVista, Software, Inc. This file is licensed under
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* the terms of the GNU General Public License version 2. This program
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* is licensed "as is" without any warranty of any kind, whether express
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* or implied.
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/module.h>
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#include <linux/spinlock.h>
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#include <linux/i2c.h>
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#include <linux/interrupt.h>
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#include <linux/mv643xx_i2c.h>
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#include <linux/platform_device.h>
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#include <linux/io.h>
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#include <linux/of.h>
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#include <linux/of_irq.h>
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#include <linux/of_i2c.h>
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#include <linux/clk.h>
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#include <linux/err.h>
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/* Register defines */
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#define MV64XXX_I2C_REG_SLAVE_ADDR 0x00
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#define MV64XXX_I2C_REG_DATA 0x04
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#define MV64XXX_I2C_REG_CONTROL 0x08
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#define MV64XXX_I2C_REG_STATUS 0x0c
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#define MV64XXX_I2C_REG_BAUD 0x0c
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#define MV64XXX_I2C_REG_EXT_SLAVE_ADDR 0x10
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#define MV64XXX_I2C_REG_SOFT_RESET 0x1c
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#define MV64XXX_I2C_REG_CONTROL_ACK 0x00000004
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#define MV64XXX_I2C_REG_CONTROL_IFLG 0x00000008
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#define MV64XXX_I2C_REG_CONTROL_STOP 0x00000010
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#define MV64XXX_I2C_REG_CONTROL_START 0x00000020
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#define MV64XXX_I2C_REG_CONTROL_TWSIEN 0x00000040
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#define MV64XXX_I2C_REG_CONTROL_INTEN 0x00000080
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/* Ctlr status values */
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#define MV64XXX_I2C_STATUS_BUS_ERR 0x00
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#define MV64XXX_I2C_STATUS_MAST_START 0x08
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#define MV64XXX_I2C_STATUS_MAST_REPEAT_START 0x10
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#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK 0x18
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#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK 0x20
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#define MV64XXX_I2C_STATUS_MAST_WR_ACK 0x28
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#define MV64XXX_I2C_STATUS_MAST_WR_NO_ACK 0x30
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#define MV64XXX_I2C_STATUS_MAST_LOST_ARB 0x38
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#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK 0x40
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#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK 0x48
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#define MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK 0x50
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#define MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK 0x58
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#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK 0xd0
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#define MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_NO_ACK 0xd8
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#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK 0xe0
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#define MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_NO_ACK 0xe8
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#define MV64XXX_I2C_STATUS_NO_STATUS 0xf8
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/* Driver states */
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enum {
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MV64XXX_I2C_STATE_INVALID,
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MV64XXX_I2C_STATE_IDLE,
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MV64XXX_I2C_STATE_WAITING_FOR_START_COND,
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MV64XXX_I2C_STATE_WAITING_FOR_RESTART,
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MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK,
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MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK,
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MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK,
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MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA,
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};
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/* Driver actions */
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enum {
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MV64XXX_I2C_ACTION_INVALID,
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MV64XXX_I2C_ACTION_CONTINUE,
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MV64XXX_I2C_ACTION_SEND_START,
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MV64XXX_I2C_ACTION_SEND_RESTART,
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MV64XXX_I2C_ACTION_SEND_ADDR_1,
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MV64XXX_I2C_ACTION_SEND_ADDR_2,
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MV64XXX_I2C_ACTION_SEND_DATA,
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MV64XXX_I2C_ACTION_RCV_DATA,
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MV64XXX_I2C_ACTION_RCV_DATA_STOP,
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MV64XXX_I2C_ACTION_SEND_STOP,
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};
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struct mv64xxx_i2c_data {
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int irq;
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u32 state;
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u32 action;
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u32 aborting;
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u32 cntl_bits;
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void __iomem *reg_base;
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u32 reg_base_p;
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u32 reg_size;
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u32 addr1;
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u32 addr2;
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u32 bytes_left;
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u32 byte_posn;
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u32 send_stop;
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u32 block;
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int rc;
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u32 freq_m;
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u32 freq_n;
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#if defined(CONFIG_HAVE_CLK)
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struct clk *clk;
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#endif
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wait_queue_head_t waitq;
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spinlock_t lock;
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struct i2c_msg *msg;
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struct i2c_adapter adapter;
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};
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/*
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*****************************************************************************
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*
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* Finite State Machine & Interrupt Routines
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*
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*****************************************************************************
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*/
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/* Reset hardware and initialize FSM */
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static void
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mv64xxx_i2c_hw_init(struct mv64xxx_i2c_data *drv_data)
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{
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writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SOFT_RESET);
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writel((((drv_data->freq_m & 0xf) << 3) | (drv_data->freq_n & 0x7)),
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drv_data->reg_base + MV64XXX_I2C_REG_BAUD);
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writel(0, drv_data->reg_base + MV64XXX_I2C_REG_SLAVE_ADDR);
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writel(0, drv_data->reg_base + MV64XXX_I2C_REG_EXT_SLAVE_ADDR);
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writel(MV64XXX_I2C_REG_CONTROL_TWSIEN | MV64XXX_I2C_REG_CONTROL_STOP,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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drv_data->state = MV64XXX_I2C_STATE_IDLE;
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}
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static void
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mv64xxx_i2c_fsm(struct mv64xxx_i2c_data *drv_data, u32 status)
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{
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/*
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* If state is idle, then this is likely the remnants of an old
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* operation that driver has given up on or the user has killed.
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* If so, issue the stop condition and go to idle.
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*/
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if (drv_data->state == MV64XXX_I2C_STATE_IDLE) {
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drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
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return;
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}
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/* The status from the ctlr [mostly] tells us what to do next */
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switch (status) {
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/* Start condition interrupt */
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case MV64XXX_I2C_STATUS_MAST_START: /* 0x08 */
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case MV64XXX_I2C_STATUS_MAST_REPEAT_START: /* 0x10 */
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drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_1;
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drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK;
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break;
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/* Performing a write */
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case MV64XXX_I2C_STATUS_MAST_WR_ADDR_ACK: /* 0x18 */
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if (drv_data->msg->flags & I2C_M_TEN) {
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drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_2;
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drv_data->state =
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MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
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break;
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}
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/* FALLTHRU */
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case MV64XXX_I2C_STATUS_MAST_WR_ADDR_2_ACK: /* 0xd0 */
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case MV64XXX_I2C_STATUS_MAST_WR_ACK: /* 0x28 */
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if ((drv_data->bytes_left == 0)
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|| (drv_data->aborting
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&& (drv_data->byte_posn != 0))) {
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if (drv_data->send_stop) {
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drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
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drv_data->state = MV64XXX_I2C_STATE_IDLE;
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} else {
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drv_data->action =
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MV64XXX_I2C_ACTION_SEND_RESTART;
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drv_data->state =
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MV64XXX_I2C_STATE_WAITING_FOR_RESTART;
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}
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} else {
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drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA;
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drv_data->state =
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MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK;
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drv_data->bytes_left--;
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}
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break;
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/* Performing a read */
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case MV64XXX_I2C_STATUS_MAST_RD_ADDR_ACK: /* 40 */
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if (drv_data->msg->flags & I2C_M_TEN) {
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drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_2;
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drv_data->state =
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MV64XXX_I2C_STATE_WAITING_FOR_ADDR_2_ACK;
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break;
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}
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/* FALLTHRU */
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case MV64XXX_I2C_STATUS_MAST_RD_ADDR_2_ACK: /* 0xe0 */
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if (drv_data->bytes_left == 0) {
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drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
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drv_data->state = MV64XXX_I2C_STATE_IDLE;
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break;
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}
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/* FALLTHRU */
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case MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK: /* 0x50 */
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if (status != MV64XXX_I2C_STATUS_MAST_RD_DATA_ACK)
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drv_data->action = MV64XXX_I2C_ACTION_CONTINUE;
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else {
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drv_data->action = MV64XXX_I2C_ACTION_RCV_DATA;
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drv_data->bytes_left--;
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}
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drv_data->state = MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA;
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if ((drv_data->bytes_left == 1) || drv_data->aborting)
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drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_ACK;
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break;
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case MV64XXX_I2C_STATUS_MAST_RD_DATA_NO_ACK: /* 0x58 */
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drv_data->action = MV64XXX_I2C_ACTION_RCV_DATA_STOP;
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drv_data->state = MV64XXX_I2C_STATE_IDLE;
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break;
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case MV64XXX_I2C_STATUS_MAST_WR_ADDR_NO_ACK: /* 0x20 */
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case MV64XXX_I2C_STATUS_MAST_WR_NO_ACK: /* 30 */
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case MV64XXX_I2C_STATUS_MAST_RD_ADDR_NO_ACK: /* 48 */
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/* Doesn't seem to be a device at other end */
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drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
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drv_data->state = MV64XXX_I2C_STATE_IDLE;
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drv_data->rc = -ENODEV;
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break;
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default:
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dev_err(&drv_data->adapter.dev,
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"mv64xxx_i2c_fsm: Ctlr Error -- state: 0x%x, "
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"status: 0x%x, addr: 0x%x, flags: 0x%x\n",
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drv_data->state, status, drv_data->msg->addr,
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drv_data->msg->flags);
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drv_data->action = MV64XXX_I2C_ACTION_SEND_STOP;
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mv64xxx_i2c_hw_init(drv_data);
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drv_data->rc = -EIO;
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}
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}
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static void
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mv64xxx_i2c_do_action(struct mv64xxx_i2c_data *drv_data)
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{
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switch(drv_data->action) {
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case MV64XXX_I2C_ACTION_SEND_RESTART:
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drv_data->cntl_bits |= MV64XXX_I2C_REG_CONTROL_START;
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drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
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writel(drv_data->cntl_bits,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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drv_data->block = 0;
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wake_up_interruptible(&drv_data->waitq);
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break;
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case MV64XXX_I2C_ACTION_CONTINUE:
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writel(drv_data->cntl_bits,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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break;
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case MV64XXX_I2C_ACTION_SEND_START:
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writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_START,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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break;
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case MV64XXX_I2C_ACTION_SEND_ADDR_1:
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writel(drv_data->addr1,
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drv_data->reg_base + MV64XXX_I2C_REG_DATA);
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writel(drv_data->cntl_bits,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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break;
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case MV64XXX_I2C_ACTION_SEND_ADDR_2:
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writel(drv_data->addr2,
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drv_data->reg_base + MV64XXX_I2C_REG_DATA);
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writel(drv_data->cntl_bits,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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break;
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case MV64XXX_I2C_ACTION_SEND_DATA:
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writel(drv_data->msg->buf[drv_data->byte_posn++],
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drv_data->reg_base + MV64XXX_I2C_REG_DATA);
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writel(drv_data->cntl_bits,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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break;
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case MV64XXX_I2C_ACTION_RCV_DATA:
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drv_data->msg->buf[drv_data->byte_posn++] =
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readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA);
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writel(drv_data->cntl_bits,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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break;
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case MV64XXX_I2C_ACTION_RCV_DATA_STOP:
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drv_data->msg->buf[drv_data->byte_posn++] =
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readl(drv_data->reg_base + MV64XXX_I2C_REG_DATA);
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drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
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writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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drv_data->block = 0;
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wake_up_interruptible(&drv_data->waitq);
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break;
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case MV64XXX_I2C_ACTION_INVALID:
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default:
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dev_err(&drv_data->adapter.dev,
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"mv64xxx_i2c_do_action: Invalid action: %d\n",
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drv_data->action);
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drv_data->rc = -EIO;
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/* FALLTHRU */
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case MV64XXX_I2C_ACTION_SEND_STOP:
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drv_data->cntl_bits &= ~MV64XXX_I2C_REG_CONTROL_INTEN;
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writel(drv_data->cntl_bits | MV64XXX_I2C_REG_CONTROL_STOP,
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drv_data->reg_base + MV64XXX_I2C_REG_CONTROL);
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drv_data->block = 0;
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wake_up_interruptible(&drv_data->waitq);
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break;
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}
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}
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static irqreturn_t
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mv64xxx_i2c_intr(int irq, void *dev_id)
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{
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struct mv64xxx_i2c_data *drv_data = dev_id;
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unsigned long flags;
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u32 status;
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irqreturn_t rc = IRQ_NONE;
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spin_lock_irqsave(&drv_data->lock, flags);
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while (readl(drv_data->reg_base + MV64XXX_I2C_REG_CONTROL) &
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MV64XXX_I2C_REG_CONTROL_IFLG) {
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status = readl(drv_data->reg_base + MV64XXX_I2C_REG_STATUS);
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mv64xxx_i2c_fsm(drv_data, status);
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mv64xxx_i2c_do_action(drv_data);
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rc = IRQ_HANDLED;
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}
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spin_unlock_irqrestore(&drv_data->lock, flags);
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|
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return rc;
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}
|
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|
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/*
|
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*****************************************************************************
|
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*
|
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* I2C Msg Execution Routines
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*
|
|
*****************************************************************************
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*/
|
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static void
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mv64xxx_i2c_prepare_for_io(struct mv64xxx_i2c_data *drv_data,
|
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struct i2c_msg *msg)
|
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{
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u32 dir = 0;
|
|
|
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drv_data->msg = msg;
|
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drv_data->byte_posn = 0;
|
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drv_data->bytes_left = msg->len;
|
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drv_data->aborting = 0;
|
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drv_data->rc = 0;
|
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drv_data->cntl_bits = MV64XXX_I2C_REG_CONTROL_ACK |
|
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MV64XXX_I2C_REG_CONTROL_INTEN | MV64XXX_I2C_REG_CONTROL_TWSIEN;
|
|
|
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if (msg->flags & I2C_M_RD)
|
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dir = 1;
|
|
|
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if (msg->flags & I2C_M_TEN) {
|
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drv_data->addr1 = 0xf0 | (((u32)msg->addr & 0x300) >> 7) | dir;
|
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drv_data->addr2 = (u32)msg->addr & 0xff;
|
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} else {
|
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drv_data->addr1 = ((u32)msg->addr & 0x7f) << 1 | dir;
|
|
drv_data->addr2 = 0;
|
|
}
|
|
}
|
|
|
|
static void
|
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mv64xxx_i2c_wait_for_completion(struct mv64xxx_i2c_data *drv_data)
|
|
{
|
|
long time_left;
|
|
unsigned long flags;
|
|
char abort = 0;
|
|
|
|
time_left = wait_event_interruptible_timeout(drv_data->waitq,
|
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!drv_data->block, drv_data->adapter.timeout);
|
|
|
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spin_lock_irqsave(&drv_data->lock, flags);
|
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if (!time_left) { /* Timed out */
|
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drv_data->rc = -ETIMEDOUT;
|
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abort = 1;
|
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} else if (time_left < 0) { /* Interrupted/Error */
|
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drv_data->rc = time_left; /* errno value */
|
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abort = 1;
|
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}
|
|
|
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if (abort && drv_data->block) {
|
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drv_data->aborting = 1;
|
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spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
|
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time_left = wait_event_timeout(drv_data->waitq,
|
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!drv_data->block, drv_data->adapter.timeout);
|
|
|
|
if ((time_left <= 0) && drv_data->block) {
|
|
drv_data->state = MV64XXX_I2C_STATE_IDLE;
|
|
dev_err(&drv_data->adapter.dev,
|
|
"mv64xxx: I2C bus locked, block: %d, "
|
|
"time_left: %d\n", drv_data->block,
|
|
(int)time_left);
|
|
mv64xxx_i2c_hw_init(drv_data);
|
|
}
|
|
} else
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
}
|
|
|
|
static int
|
|
mv64xxx_i2c_execute_msg(struct mv64xxx_i2c_data *drv_data, struct i2c_msg *msg,
|
|
int is_first, int is_last)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&drv_data->lock, flags);
|
|
mv64xxx_i2c_prepare_for_io(drv_data, msg);
|
|
|
|
if (unlikely(msg->flags & I2C_M_NOSTART)) { /* Skip start/addr phases */
|
|
if (drv_data->msg->flags & I2C_M_RD) {
|
|
/* No action to do, wait for slave to send a byte */
|
|
drv_data->action = MV64XXX_I2C_ACTION_CONTINUE;
|
|
drv_data->state =
|
|
MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_DATA;
|
|
} else {
|
|
drv_data->action = MV64XXX_I2C_ACTION_SEND_DATA;
|
|
drv_data->state =
|
|
MV64XXX_I2C_STATE_WAITING_FOR_SLAVE_ACK;
|
|
drv_data->bytes_left--;
|
|
}
|
|
} else {
|
|
if (is_first) {
|
|
drv_data->action = MV64XXX_I2C_ACTION_SEND_START;
|
|
drv_data->state =
|
|
MV64XXX_I2C_STATE_WAITING_FOR_START_COND;
|
|
} else {
|
|
drv_data->action = MV64XXX_I2C_ACTION_SEND_ADDR_1;
|
|
drv_data->state =
|
|
MV64XXX_I2C_STATE_WAITING_FOR_ADDR_1_ACK;
|
|
}
|
|
}
|
|
|
|
drv_data->send_stop = is_last;
|
|
drv_data->block = 1;
|
|
mv64xxx_i2c_do_action(drv_data);
|
|
spin_unlock_irqrestore(&drv_data->lock, flags);
|
|
|
|
mv64xxx_i2c_wait_for_completion(drv_data);
|
|
return drv_data->rc;
|
|
}
|
|
|
|
/*
|
|
*****************************************************************************
|
|
*
|
|
* I2C Core Support Routines (Interface to higher level I2C code)
|
|
*
|
|
*****************************************************************************
|
|
*/
|
|
static u32
|
|
mv64xxx_i2c_functionality(struct i2c_adapter *adap)
|
|
{
|
|
return I2C_FUNC_I2C | I2C_FUNC_10BIT_ADDR | I2C_FUNC_SMBUS_EMUL;
|
|
}
|
|
|
|
static int
|
|
mv64xxx_i2c_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
|
|
{
|
|
struct mv64xxx_i2c_data *drv_data = i2c_get_adapdata(adap);
|
|
int i, rc;
|
|
|
|
for (i = 0; i < num; i++) {
|
|
rc = mv64xxx_i2c_execute_msg(drv_data, &msgs[i],
|
|
i == 0, i + 1 == num);
|
|
if (rc < 0)
|
|
return rc;
|
|
}
|
|
|
|
return num;
|
|
}
|
|
|
|
static const struct i2c_algorithm mv64xxx_i2c_algo = {
|
|
.master_xfer = mv64xxx_i2c_xfer,
|
|
.functionality = mv64xxx_i2c_functionality,
|
|
};
|
|
|
|
/*
|
|
*****************************************************************************
|
|
*
|
|
* Driver Interface & Early Init Routines
|
|
*
|
|
*****************************************************************************
|
|
*/
|
|
static int
|
|
mv64xxx_i2c_map_regs(struct platform_device *pd,
|
|
struct mv64xxx_i2c_data *drv_data)
|
|
{
|
|
int size;
|
|
struct resource *r = platform_get_resource(pd, IORESOURCE_MEM, 0);
|
|
|
|
if (!r)
|
|
return -ENODEV;
|
|
|
|
size = resource_size(r);
|
|
|
|
if (!request_mem_region(r->start, size, drv_data->adapter.name))
|
|
return -EBUSY;
|
|
|
|
drv_data->reg_base = ioremap(r->start, size);
|
|
drv_data->reg_base_p = r->start;
|
|
drv_data->reg_size = size;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void
|
|
mv64xxx_i2c_unmap_regs(struct mv64xxx_i2c_data *drv_data)
|
|
{
|
|
if (drv_data->reg_base) {
|
|
iounmap(drv_data->reg_base);
|
|
release_mem_region(drv_data->reg_base_p, drv_data->reg_size);
|
|
}
|
|
|
|
drv_data->reg_base = NULL;
|
|
drv_data->reg_base_p = 0;
|
|
}
|
|
|
|
#ifdef CONFIG_OF
|
|
static int
|
|
mv64xxx_calc_freq(const int tclk, const int n, const int m)
|
|
{
|
|
return tclk / (10 * (m + 1) * (2 << n));
|
|
}
|
|
|
|
static bool
|
|
mv64xxx_find_baud_factors(const u32 req_freq, const u32 tclk, u32 *best_n,
|
|
u32 *best_m)
|
|
{
|
|
int freq, delta, best_delta = INT_MAX;
|
|
int m, n;
|
|
|
|
for (n = 0; n <= 7; n++)
|
|
for (m = 0; m <= 15; m++) {
|
|
freq = mv64xxx_calc_freq(tclk, n, m);
|
|
delta = req_freq - freq;
|
|
if (delta >= 0 && delta < best_delta) {
|
|
*best_m = m;
|
|
*best_n = n;
|
|
best_delta = delta;
|
|
}
|
|
if (best_delta == 0)
|
|
return true;
|
|
}
|
|
if (best_delta == INT_MAX)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
static int
|
|
mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
|
|
struct device_node *np)
|
|
{
|
|
u32 bus_freq, tclk;
|
|
int rc = 0;
|
|
|
|
/* CLK is mandatory when using DT to describe the i2c bus. We
|
|
* need to know tclk in order to calculate bus clock
|
|
* factors.
|
|
*/
|
|
#if !defined(CONFIG_HAVE_CLK)
|
|
/* Have OF but no CLK */
|
|
return -ENODEV;
|
|
#else
|
|
if (IS_ERR(drv_data->clk)) {
|
|
rc = -ENODEV;
|
|
goto out;
|
|
}
|
|
tclk = clk_get_rate(drv_data->clk);
|
|
of_property_read_u32(np, "clock-frequency", &bus_freq);
|
|
if (!mv64xxx_find_baud_factors(bus_freq, tclk,
|
|
&drv_data->freq_n, &drv_data->freq_m)) {
|
|
rc = -EINVAL;
|
|
goto out;
|
|
}
|
|
drv_data->irq = irq_of_parse_and_map(np, 0);
|
|
|
|
/* Its not yet defined how timeouts will be specified in device tree.
|
|
* So hard code the value to 1 second.
|
|
*/
|
|
drv_data->adapter.timeout = HZ;
|
|
out:
|
|
return rc;
|
|
#endif
|
|
}
|
|
#else /* CONFIG_OF */
|
|
static int
|
|
mv64xxx_of_config(struct mv64xxx_i2c_data *drv_data,
|
|
struct device_node *np)
|
|
{
|
|
return -ENODEV;
|
|
}
|
|
#endif /* CONFIG_OF */
|
|
|
|
static int
|
|
mv64xxx_i2c_probe(struct platform_device *pd)
|
|
{
|
|
struct mv64xxx_i2c_data *drv_data;
|
|
struct mv64xxx_i2c_pdata *pdata = pd->dev.platform_data;
|
|
int rc;
|
|
|
|
if ((!pdata && !pd->dev.of_node))
|
|
return -ENODEV;
|
|
|
|
drv_data = kzalloc(sizeof(struct mv64xxx_i2c_data), GFP_KERNEL);
|
|
if (!drv_data)
|
|
return -ENOMEM;
|
|
|
|
if (mv64xxx_i2c_map_regs(pd, drv_data)) {
|
|
rc = -ENODEV;
|
|
goto exit_kfree;
|
|
}
|
|
|
|
strlcpy(drv_data->adapter.name, MV64XXX_I2C_CTLR_NAME " adapter",
|
|
sizeof(drv_data->adapter.name));
|
|
|
|
init_waitqueue_head(&drv_data->waitq);
|
|
spin_lock_init(&drv_data->lock);
|
|
|
|
#if defined(CONFIG_HAVE_CLK)
|
|
/* Not all platforms have a clk */
|
|
drv_data->clk = clk_get(&pd->dev, NULL);
|
|
if (!IS_ERR(drv_data->clk)) {
|
|
clk_prepare(drv_data->clk);
|
|
clk_enable(drv_data->clk);
|
|
}
|
|
#endif
|
|
if (pdata) {
|
|
drv_data->freq_m = pdata->freq_m;
|
|
drv_data->freq_n = pdata->freq_n;
|
|
drv_data->irq = platform_get_irq(pd, 0);
|
|
drv_data->adapter.timeout = msecs_to_jiffies(pdata->timeout);
|
|
} else if (pd->dev.of_node) {
|
|
rc = mv64xxx_of_config(drv_data, pd->dev.of_node);
|
|
if (rc)
|
|
goto exit_unmap_regs;
|
|
}
|
|
if (drv_data->irq < 0) {
|
|
rc = -ENXIO;
|
|
goto exit_unmap_regs;
|
|
}
|
|
|
|
drv_data->adapter.dev.parent = &pd->dev;
|
|
drv_data->adapter.algo = &mv64xxx_i2c_algo;
|
|
drv_data->adapter.owner = THIS_MODULE;
|
|
drv_data->adapter.class = I2C_CLASS_HWMON | I2C_CLASS_SPD;
|
|
drv_data->adapter.nr = pd->id;
|
|
drv_data->adapter.dev.of_node = pd->dev.of_node;
|
|
platform_set_drvdata(pd, drv_data);
|
|
i2c_set_adapdata(&drv_data->adapter, drv_data);
|
|
|
|
mv64xxx_i2c_hw_init(drv_data);
|
|
|
|
if (request_irq(drv_data->irq, mv64xxx_i2c_intr, 0,
|
|
MV64XXX_I2C_CTLR_NAME, drv_data)) {
|
|
dev_err(&drv_data->adapter.dev,
|
|
"mv64xxx: Can't register intr handler irq: %d\n",
|
|
drv_data->irq);
|
|
rc = -EINVAL;
|
|
goto exit_unmap_regs;
|
|
} else if ((rc = i2c_add_numbered_adapter(&drv_data->adapter)) != 0) {
|
|
dev_err(&drv_data->adapter.dev,
|
|
"mv64xxx: Can't add i2c adapter, rc: %d\n", -rc);
|
|
goto exit_free_irq;
|
|
}
|
|
|
|
of_i2c_register_devices(&drv_data->adapter);
|
|
|
|
return 0;
|
|
|
|
exit_free_irq:
|
|
free_irq(drv_data->irq, drv_data);
|
|
exit_unmap_regs:
|
|
#if defined(CONFIG_HAVE_CLK)
|
|
/* Not all platforms have a clk */
|
|
if (!IS_ERR(drv_data->clk)) {
|
|
clk_disable(drv_data->clk);
|
|
clk_unprepare(drv_data->clk);
|
|
}
|
|
#endif
|
|
mv64xxx_i2c_unmap_regs(drv_data);
|
|
exit_kfree:
|
|
kfree(drv_data);
|
|
return rc;
|
|
}
|
|
|
|
static int
|
|
mv64xxx_i2c_remove(struct platform_device *dev)
|
|
{
|
|
struct mv64xxx_i2c_data *drv_data = platform_get_drvdata(dev);
|
|
|
|
i2c_del_adapter(&drv_data->adapter);
|
|
free_irq(drv_data->irq, drv_data);
|
|
mv64xxx_i2c_unmap_regs(drv_data);
|
|
#if defined(CONFIG_HAVE_CLK)
|
|
/* Not all platforms have a clk */
|
|
if (!IS_ERR(drv_data->clk)) {
|
|
clk_disable(drv_data->clk);
|
|
clk_unprepare(drv_data->clk);
|
|
}
|
|
#endif
|
|
kfree(drv_data);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id mv64xxx_i2c_of_match_table[] = {
|
|
{ .compatible = "marvell,mv64xxx-i2c", },
|
|
{}
|
|
};
|
|
MODULE_DEVICE_TABLE(of, mv64xxx_i2c_of_match_table);
|
|
|
|
static struct platform_driver mv64xxx_i2c_driver = {
|
|
.probe = mv64xxx_i2c_probe,
|
|
.remove = mv64xxx_i2c_remove,
|
|
.driver = {
|
|
.owner = THIS_MODULE,
|
|
.name = MV64XXX_I2C_CTLR_NAME,
|
|
.of_match_table = of_match_ptr(mv64xxx_i2c_of_match_table),
|
|
},
|
|
};
|
|
|
|
module_platform_driver(mv64xxx_i2c_driver);
|
|
|
|
MODULE_AUTHOR("Mark A. Greer <mgreer@mvista.com>");
|
|
MODULE_DESCRIPTION("Marvell mv64xxx host bridge i2c ctlr driver");
|
|
MODULE_LICENSE("GPL");
|