diff options
Diffstat (limited to 'drivers/power/pm2301_charger.c')
| -rw-r--r-- | drivers/power/pm2301_charger.c | 71 |
1 files changed, 69 insertions, 2 deletions
diff --git a/drivers/power/pm2301_charger.c b/drivers/power/pm2301_charger.c index 9b2e8943f94..ed48d75bb78 100644 --- a/drivers/power/pm2301_charger.c +++ b/drivers/power/pm2301_charger.c @@ -28,6 +28,7 @@ #include <linux/mfd/abx500/ab8500-gpadc.h> #include <linux/mfd/abx500/ux500_chargalg.h> #include <linux/pm2301_charger.h> +#include <linux/gpio.h> #include "pm2301_charger.h" @@ -110,9 +111,35 @@ static const struct i2c_device_id pm2xxx_ident[] = { { } }; +static void set_lpn_pin(struct pm2xxx_charger *pm2) +{ + if (pm2->ac.charger_connected) + return; + gpio_set_value(pm2->lpn_pin, 1); + + return; +} + +static void clear_lpn_pin(struct pm2xxx_charger *pm2) +{ + if (pm2->ac.charger_connected) + return; + gpio_set_value(pm2->lpn_pin, 0); + + return; +} + static int pm2xxx_reg_read(struct pm2xxx_charger *pm2, int reg, u8 *val) { int ret; + /* + * When AC adaptor is unplugged, the host + * must put LPN high to be able to + * communicate by I2C with PM2301 + * and receive I2C "acknowledge" from PM2301. + */ + mutex_lock(&pm2->lock); + set_lpn_pin(pm2); ret = i2c_smbus_read_i2c_block_data(pm2->config.pm2xxx_i2c, reg, 1, val); @@ -120,6 +147,8 @@ static int pm2xxx_reg_read(struct pm2xxx_charger *pm2, int reg, u8 *val) dev_err(pm2->dev, "Error reading register at 0x%x\n", reg); else ret = 0; + clear_lpn_pin(pm2); + mutex_unlock(&pm2->lock); return ret; } @@ -127,6 +156,14 @@ static int pm2xxx_reg_read(struct pm2xxx_charger *pm2, int reg, u8 *val) static int pm2xxx_reg_write(struct pm2xxx_charger *pm2, int reg, u8 val) { int ret; + /* + * When AC adaptor is unplugged, the host + * must put LPN high to be able to + * communicate by I2C with PM2301 + * and receive I2C "acknowledge" from PM2301. + */ + mutex_lock(&pm2->lock); + set_lpn_pin(pm2); ret = i2c_smbus_write_i2c_block_data(pm2->config.pm2xxx_i2c, reg, 1, &val); @@ -134,6 +171,8 @@ static int pm2xxx_reg_write(struct pm2xxx_charger *pm2, int reg, u8 val) dev_err(pm2->dev, "Error writing register at 0x%x\n", reg); else ret = 0; + clear_lpn_pin(pm2); + mutex_unlock(&pm2->lock); return ret; } @@ -850,6 +889,14 @@ static int __devinit pm2xxx_wall_charger_probe(struct i2c_client *i2c_client, pm2->bat = pl_data->battery; + /*get lpn GPIO from platform data*/ + if (!pm2->pdata->lpn_gpio) { + dev_err(pm2->dev, "no lpn gpio data supplied\n"); + ret = -EINVAL; + goto free_device_info; + } + pm2->lpn_pin = pm2->pdata->lpn_gpio; + if (!i2c_check_functionality(i2c_client->adapter, I2C_FUNC_SMBUS_BYTE_DATA | I2C_FUNC_SMBUS_READ_WORD_DATA)) { @@ -929,10 +976,25 @@ static int __devinit pm2xxx_wall_charger_probe(struct i2c_client *i2c_client, goto unregister_pm2xxx_charger; } + /*Initialize lock*/ + mutex_init(&pm2->lock); + /* - * I2C Read/Write will fail, if AC adaptor is not connected. - * fix the charger detection mechanism. + * Charger detection mechanism requires pulling up the LPN pin + * while i2c communication if Charger is not connected + * LPN pin of PM2301 is GPIO60 of AB9540 */ + ret = gpio_request(pm2->lpn_pin, "pm2301_lpm_gpio"); + if (ret < 0) { + dev_err(pm2->dev, "pm2301_lpm_gpio request failed\n"); + goto unregister_pm2xxx_charger; + } + ret = gpio_direction_output(pm2->lpn_pin, 0); + if (ret < 0) { + dev_err(pm2->dev, "pm2301_lpm_gpio direction failed\n"); + goto free_gpio; + } + ret = pm2xxx_charger_detection(pm2, &val); if ((ret == 0) && val) { @@ -944,6 +1006,8 @@ static int __devinit pm2xxx_wall_charger_probe(struct i2c_client *i2c_client, return 0; +free_gpio: + gpio_free(pm2->lpn_pin); unregister_pm2xxx_charger: /* unregister power supply */ power_supply_unregister(&pm2->ac_chg.psy); @@ -977,6 +1041,9 @@ static int __devexit pm2xxx_wall_charger_remove(struct i2c_client *i2c_client) power_supply_unregister(&pm2->ac_chg.psy); + /*Free GPIO60*/ + gpio_free(pm2->lpn_pin); + kfree(pm2); return 0; |