From 547120edbacba09ae8becab65aa86e3fd4e75e9a Mon Sep 17 00:00:00 2001 From: Steve Twiss Date: Wed, 6 Jul 2016 16:12:03 +0100 Subject: [PATCH] mfd: da9053: Ensure the FAULT_LOG is cleared during MFD driver probe The function da9052_clear_fault_log() is added to mitigate the case of persistent data being transferred between reboots. Clearance of any the persistent information within the DA9053 FAULT_LOG register must be completed during start-up so the fault-log does not continue with previous values. A clearance function has been added here in the kernel driver because wiping the fault-log cannot be counted on outside the Linux kernel. Signed-off-by: Steve Twiss Reviewed-by: Adam Thomson Signed-off-by: Lee Jones --- drivers/mfd/da9052-core.c | 51 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 51 insertions(+) diff --git a/drivers/mfd/da9052-core.c b/drivers/mfd/da9052-core.c index c0bf68a3e614..a88c2065d8ab 100644 --- a/drivers/mfd/da9052-core.c +++ b/drivers/mfd/da9052-core.c @@ -167,6 +167,7 @@ static bool da9052_reg_writeable(struct device *dev, unsigned int reg) case DA9052_EVENT_B_REG: case DA9052_EVENT_C_REG: case DA9052_EVENT_D_REG: + case DA9052_FAULTLOG_REG: case DA9052_IRQ_MASK_A_REG: case DA9052_IRQ_MASK_B_REG: case DA9052_IRQ_MASK_C_REG: @@ -541,6 +542,52 @@ const struct regmap_config da9052_regmap_config = { }; EXPORT_SYMBOL_GPL(da9052_regmap_config); +static int da9052_clear_fault_log(struct da9052 *da9052) +{ + int ret = 0; + int fault_log = 0; + + fault_log = da9052_reg_read(da9052, DA9052_FAULTLOG_REG); + if (fault_log < 0) { + dev_err(da9052->dev, + "Cannot read FAULT_LOG %d\n", fault_log); + return fault_log; + } + + if (fault_log) { + if (fault_log & DA9052_FAULTLOG_TWDERROR) + dev_dbg(da9052->dev, + "Fault log entry detected: TWD_ERROR\n"); + if (fault_log & DA9052_FAULTLOG_VDDFAULT) + dev_dbg(da9052->dev, + "Fault log entry detected: VDD_FAULT\n"); + if (fault_log & DA9052_FAULTLOG_VDDSTART) + dev_dbg(da9052->dev, + "Fault log entry detected: VDD_START\n"); + if (fault_log & DA9052_FAULTLOG_TEMPOVER) + dev_dbg(da9052->dev, + "Fault log entry detected: TEMP_OVER\n"); + if (fault_log & DA9052_FAULTLOG_KEYSHUT) + dev_dbg(da9052->dev, + "Fault log entry detected: KEY_SHUT\n"); + if (fault_log & DA9052_FAULTLOG_NSDSET) + dev_dbg(da9052->dev, + "Fault log entry detected: nSD_SHUT\n"); + if (fault_log & DA9052_FAULTLOG_WAITSET) + dev_dbg(da9052->dev, + "Fault log entry detected: WAIT_SHUT\n"); + + ret = da9052_reg_write(da9052, + DA9052_FAULTLOG_REG, + 0xFF); + if (ret < 0) + dev_err(da9052->dev, + "Cannot reset FAULT_LOG values %d\n", ret); + } + + return ret; +} + int da9052_device_init(struct da9052 *da9052, u8 chip_id) { struct da9052_pdata *pdata = dev_get_platdata(da9052->dev); @@ -549,6 +596,10 @@ int da9052_device_init(struct da9052 *da9052, u8 chip_id) mutex_init(&da9052->auxadc_lock); init_completion(&da9052->done); + ret = da9052_clear_fault_log(da9052); + if (ret < 0) + dev_warn(da9052->dev, "Cannot clear FAULT_LOG\n"); + if (pdata && pdata->init != NULL) pdata->init(da9052); -- 2.39.2