pm2301: LPN mode control support

The AC charger plug-in detection while booting causes I2C read
failure if AC charger is not connected. Now the LPN pin is enabled
for every PM2301 register access, which solves the issue.

Signed-off-by: Rupesh Kumar <rupesh.kumar@stericsson.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Reviewed-by: Marcus COOPER <marcus.xm.cooper@stericsson.com>
Reviewed-by: Vijaya Kumar K-1 <vijay.kilari@stericsson.com>
Reviewed-by: Rabin VINCENT <rabin.vincent@stericsson.com>
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>
Tested-by: Jonas ABERG <jonas.aberg@stericsson.com>
This commit is contained in:
Lee Jones 2013-01-23 14:38:15 +00:00
parent e41f39ea2a
commit 3988043b0e
3 changed files with 71 additions and 2 deletions

View file

@ -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;

View file

@ -493,6 +493,7 @@ struct pm2xxx_charger {
int old_vbat;
int failure_case;
int failure_input_ovv;
unsigned int lpn_pin;
struct pm2xxx_interrupts *pm2_int;
struct ab8500_gpadc *gpadc;
struct regulator *regu;

View file

@ -49,6 +49,7 @@ struct pm2xxx_charger_platform_data {
int i2c_bus;
const char *label;
int irq_number;
unsigned int lpn_gpio;
int irq_type;
};