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| author | David Jander <david@protonic.nl> | 2013-09-02 09:46:11 +0200 |
|---|---|---|
| committer | Lee Jones <lee.jones@linaro.org> | 2013-10-23 17:20:32 +0200 |
| commit | 43e30f23b589642a7eaff005bc30444a5247976c (patch) | |
| tree | a8c467e71306d5cea46c52ecd795839bb7438832 | |
| parent | Linux 3.12-rc5 (diff) | |
| download | linux-43e30f23b589642a7eaff005bc30444a5247976c.tar.xz linux-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>
| -rw-r--r-- | drivers/mfd/da9052-i2c.c | 12 | ||||
| -rw-r--r-- | include/linux/mfd/da9052/da9052.h | 20 |
2 files changed, 22 insertions, 10 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; diff --git a/include/linux/mfd/da9052/da9052.h b/include/linux/mfd/da9052/da9052.h index 786d02eb79d2..21e21b81cc75 100644 --- a/include/linux/mfd/da9052/da9052.h +++ b/include/linux/mfd/da9052/da9052.h @@ -148,10 +148,15 @@ static inline int da9052_group_read(struct da9052 *da9052, unsigned char reg, unsigned reg_cnt, unsigned char *val) { int ret; + unsigned int tmp; + int i; - ret = regmap_bulk_read(da9052->regmap, reg, val, reg_cnt); - if (ret < 0) - return ret; + for (i = 0; i < reg_cnt; i++) { + ret = regmap_read(da9052->regmap, reg + i, &tmp); + val[i] = (unsigned char)tmp; + if (ret < 0) + return ret; + } if (da9052->fix_io) { ret = da9052->fix_io(da9052, reg); @@ -166,10 +171,13 @@ static inline int da9052_group_write(struct da9052 *da9052, unsigned char reg, unsigned reg_cnt, unsigned char *val) { int ret; + int i; - ret = regmap_raw_write(da9052->regmap, reg, val, reg_cnt); - if (ret < 0) - return ret; + for (i = 0; i < reg_cnt; i++) { + ret = regmap_write(da9052->regmap, reg + i, val[i]); + if (ret < 0) + return ret; + } if (da9052->fix_io) { ret = da9052->fix_io(da9052, reg); |