diff options
| author | David Jander <david@protonic.nl> | 2013-09-02 09:46:11 +0200 |
|---|---|---|
| committer | Lee Jones <lee.jones@linaro.org> | 2013-10-23 16:20:32 +0100 |
| commit | 43e30f23b589642a7eaff005bc30444a5247976c (patch) | |
| tree | a8c467e71306d5cea46c52ecd795839bb7438832 /drivers/mfd/da9052-i2c.c | |
| parent | 61e6cfa80de5760bbe406f4e815b7739205754d2 (diff) | |
| download | lwn-43e30f23b589642a7eaff005bc30444a5247976c.tar.gz lwn-43e30f23b589642a7eaff005bc30444a5247976c.zip | |
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 <david@protonic.nl>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Diffstat (limited to 'drivers/mfd/da9052-i2c.c')
| -rw-r--r-- | drivers/mfd/da9052-i2c.c | 12 |
1 files changed, 8 insertions, 4 deletions
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; |