From a22b41a31e5382792151f193d185a3cd39593cfd Mon Sep 17 00:00:00 2001 From: Olof Johansson Date: Thu, 6 Sep 2012 11:32:29 -0700 Subject: [PATCH] sbs-battery: Probe should try talking to the device Turns out this driver doesn't actually try talking to the device at probe time, so if it's incorrectly configured in the device tree or platform data (or if the battery has been removed from the system), then probe will succeed and every access will sit there and time out. The end result is a possibly laggy system that thinks it has a battery but can never read status, which isn't very useful. Instead, just read any register (I chose status) at probe, and if that fails, don't register the device. Signed-off-by: Olof Johansson Acked-by: Rhyland Klein Signed-off-by: Anton Vorontsov --- drivers/power/sbs-battery.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/power/sbs-battery.c b/drivers/power/sbs-battery.c index a65e8f54157e..4146596d254b 100644 --- a/drivers/power/sbs-battery.c +++ b/drivers/power/sbs-battery.c @@ -759,6 +759,16 @@ static int __devinit sbs_probe(struct i2c_client *client, chip->irq = irq; skip_gpio: + /* + * Before we register, we need to make sure we can actually talk + * to the battery. + */ + rc = sbs_read_word_data(client, sbs_data[REG_STATUS].addr); + if (rc < 0) { + dev_err(&client->dev, "%s: Failed to get device status\n", + __func__); + goto exit_psupply; + } rc = power_supply_register(&client->dev, &chip->power_supply); if (rc) {