[media] smiapp: Quirk for sensors that only do 8-bit reads

Some sensors implement only 8-bit read functionality and fail on wider
reads. Add a quirk flag for such sensors.

Signed-off-by: Sakari Ailus <sakari.ailus@maxwell.research.nokia.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Sakari Ailus 2012-04-22 09:11:26 -03:00 committed by Mauro Carvalho Chehab
parent 1e73eea781
commit ceb9e30e9f
3 changed files with 66 additions and 9 deletions

View File

@ -46,6 +46,7 @@ struct smiapp_quirk {
/* op pix clock is for all lanes in total normally */
#define SMIAPP_QUIRK_FLAG_OP_PIX_CLOCK_PER_LANE (1 << 0)
#define SMIAPP_QUIRK_FLAG_8BIT_READ_ONLY (1 << 1)
struct smiapp_reg_8 {
u16 reg;

View File

@ -78,19 +78,15 @@ static uint32_t float_to_u32_mul_1000000(struct i2c_client *client,
* Read a 8/16/32-bit i2c register. The value is returned in 'val'.
* Returns zero if successful, or non-zero otherwise.
*/
int smiapp_read(struct smiapp_sensor *sensor, u32 reg, u32 *val)
static int ____smiapp_read(struct smiapp_sensor *sensor, u16 reg,
u16 len, u32 *val)
{
struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd);
struct i2c_msg msg;
unsigned char data[4];
unsigned int len = (u8)(reg >> 16);
u16 offset = reg;
int r;
if (len != SMIA_REG_8BIT && len != SMIA_REG_16BIT
&& len != SMIA_REG_32BIT)
return -EINVAL;
msg.addr = client->addr;
msg.flags = 0;
msg.len = 2;
@ -132,9 +128,6 @@ int smiapp_read(struct smiapp_sensor *sensor, u32 reg, u32 *val)
BUG();
}
if (reg & SMIA_REG_FLAG_FLOAT)
*val = float_to_u32_mul_1000000(client, *val);
return 0;
err:
@ -143,6 +136,68 @@ err:
return r;
}
/* Read a register using 8-bit access only. */
static int ____smiapp_read_8only(struct smiapp_sensor *sensor, u16 reg,
u16 len, u32 *val)
{
unsigned int i;
int rval;
*val = 0;
for (i = 0; i < len; i++) {
u32 val8;
rval = ____smiapp_read(sensor, reg + i, 1, &val8);
if (rval < 0)
return rval;
*val |= val8 << ((len - i - 1) << 3);
}
return 0;
}
/*
* Read a 8/16/32-bit i2c register. The value is returned in 'val'.
* Returns zero if successful, or non-zero otherwise.
*/
static int __smiapp_read(struct smiapp_sensor *sensor, u32 reg, u32 *val,
bool only8)
{
struct i2c_client *client = v4l2_get_subdevdata(&sensor->src->sd);
unsigned int len = (u8)(reg >> 16);
int rval;
if (len != SMIA_REG_8BIT && len != SMIA_REG_16BIT
&& len != SMIA_REG_32BIT)
return -EINVAL;
if (len == SMIA_REG_8BIT && !only8)
rval = ____smiapp_read(sensor, (u16)reg, len, val);
else
rval = ____smiapp_read_8only(sensor, (u16)reg, len, val);
if (rval < 0)
return rval;
if (reg & SMIA_REG_FLAG_FLOAT)
*val = float_to_u32_mul_1000000(client, *val);
return 0;
}
int smiapp_read(struct smiapp_sensor *sensor, u32 reg, u32 *val)
{
return __smiapp_read(
sensor, reg, val,
smiapp_needs_quirk(sensor,
SMIAPP_QUIRK_FLAG_8BIT_READ_ONLY));
}
int smiapp_read_8only(struct smiapp_sensor *sensor, u32 reg, u32 *val)
{
return __smiapp_read(sensor, reg, val, true);
}
/*
* Write to a 8/16-bit register.
* Returns zero if successful, or non-zero otherwise.

View File

@ -43,6 +43,7 @@ struct smia_reg {
struct smiapp_sensor;
int smiapp_read(struct smiapp_sensor *sensor, u32 reg, u32 *val);
int smiapp_read_8only(struct smiapp_sensor *sensor, u32 reg, u32 *val);
int smiapp_write(struct smiapp_sensor *sensor, u32 reg, u32 val);
#endif