Revert "power: supply: sbs-battery: simplify read_read_string_data"
The commit is a nice cleanup, but breaks booting on exynos5 based
chromebooks. It's seems to come down to exynos5's i2c driver not
implementing I2C_FUNC_SMBUS_READ_BLOCK_DATA. It's not yet clear
why that breaks boot / massively slows it down when userspace
starts, so revert the problematic patch.
This reverts commit c4b12a2f3f3de670f6be5e96092a2cab0b877f1a.
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
diff --git a/drivers/power/supply/sbs-battery.c b/drivers/power/supply/sbs-battery.c
index 00dfd9e..83b9924 100644
--- a/drivers/power/supply/sbs-battery.c
+++ b/drivers/power/supply/sbs-battery.c
@@ -267,32 +267,66 @@ static int sbs_read_string_data(struct i2c_client *client, u8 address,
char *values)
{
struct sbs_info *chip = i2c_get_clientdata(client);
- int retries = chip->i2c_retry_count;
- s32 ret = 0;
+ s32 ret = 0, block_length = 0;
+ int retries_length, retries_block;
+ u8 block_buffer[I2C_SMBUS_BLOCK_MAX + 1];
+ retries_length = chip->i2c_retry_count;
+ retries_block = chip->i2c_retry_count;
+
+ /* Adapter needs to support these two functions */
if (!i2c_check_functionality(client->adapter,
- I2C_FUNC_SMBUS_READ_BLOCK_DATA)) {
+ I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_I2C_BLOCK)){
return -ENODEV;
}
- /* Get the block data */
- while (retries > 0) {
- ret = i2c_smbus_read_block_data(client, address, values);
+ /* Get the length of block data */
+ while (retries_length > 0) {
+ ret = i2c_smbus_read_byte_data(client, address);
if (ret >= 0)
break;
- retries--;
+ retries_length--;
}
if (ret < 0) {
- dev_dbg(&client->dev, "%s: failed to read block 0x%x: %d\n",
- __func__, address, ret);
+ dev_dbg(&client->dev,
+ "%s: i2c read at address 0x%x failed\n",
+ __func__, address);
return ret;
}
- /* add string termination */
- values[ret] = '\0';
+ /* block_length does not include NULL terminator */
+ block_length = ret;
+ if (block_length > I2C_SMBUS_BLOCK_MAX) {
+ dev_err(&client->dev,
+ "%s: Returned block_length is longer than 0x%x\n",
+ __func__, I2C_SMBUS_BLOCK_MAX);
+ return -EINVAL;
+ }
- return 0;
+ /* Get the block data */
+ while (retries_block > 0) {
+ ret = i2c_smbus_read_i2c_block_data(
+ client, address,
+ block_length + 1, block_buffer);
+ if (ret >= 0)
+ break;
+ retries_block--;
+ }
+
+ if (ret < 0) {
+ dev_dbg(&client->dev,
+ "%s: i2c read at address 0x%x failed\n",
+ __func__, address);
+ return ret;
+ }
+
+ /* block_buffer[0] == block_length */
+ memcpy(values, block_buffer + 1, block_length);
+ values[block_length] = '\0';
+
+ return ret;
}
static int sbs_write_word_data(struct i2c_client *client, u8 address,
@@ -514,7 +548,14 @@ static int sbs_get_battery_property(struct i2c_client *client,
static int sbs_get_battery_string_property(struct i2c_client *client,
int reg_offset, enum power_supply_property psp, char *val)
{
- return sbs_read_string_data(client, sbs_data[reg_offset].addr, val);
+ s32 ret;
+
+ ret = sbs_read_string_data(client, sbs_data[reg_offset].addr, val);
+
+ if (ret < 0)
+ return ret;
+
+ return 0;
}
static void sbs_unit_adjustment(struct i2c_client *client,
