From 43e30f23b589642a7eaff005bc30444a5247976c Mon Sep 17 00:00:00 2001 From: David Jander Date: Mon, 2 Sep 2013 09:46:11 +0200 Subject: mfd: da9052: Avoid multiwrite mode due to silicon errata DA9053 (up to revision bc) can corrupt internal registers when multi-write mode is enabled and power is removed or during shutdown. Signed-off-by: David Jander Signed-off-by: Lee Jones --- drivers/mfd/da9052-i2c.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'drivers/mfd/da9052-i2c.c') diff --git a/drivers/mfd/da9052-i2c.c b/drivers/mfd/da9052-i2c.c index 6a9fec40d018..c319c4ef5d49 100644 --- a/drivers/mfd/da9052-i2c.c +++ b/drivers/mfd/da9052-i2c.c @@ -86,7 +86,11 @@ static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg) return 0; } -static int da9052_i2c_enable_multiwrite(struct da9052 *da9052) +/* + * According to errata item 24, multiwrite mode should be avoided + * in order to prevent register data corruption after power-down. + */ +static int da9052_i2c_disable_multiwrite(struct da9052 *da9052) { int reg_val, ret; @@ -94,8 +98,8 @@ static int da9052_i2c_enable_multiwrite(struct da9052 *da9052) if (ret < 0) return ret; - if (reg_val & DA9052_CONTROL_B_WRITEMODE) { - reg_val &= ~DA9052_CONTROL_B_WRITEMODE; + if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) { + reg_val |= DA9052_CONTROL_B_WRITEMODE; ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG, reg_val); if (ret < 0) @@ -154,7 +158,7 @@ static int da9052_i2c_probe(struct i2c_client *client, return ret; } - ret = da9052_i2c_enable_multiwrite(da9052); + ret = da9052_i2c_disable_multiwrite(da9052); if (ret < 0) return ret; -- cgit v1.2.3