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media: ccs: Try a little longer to access the sensor before giving up

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Some sensors take longer to respond after reset than the spec-required
time. Try up to 1 s for the sensor to become accessible.

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
This commit is contained in:
Sakari Ailus
2024-10-15 09:59:52 +03:00
committed by Hans Verkuil
parent 5bd6b8c1bb
commit e848475c33
2 changed files with 15 additions and 13 deletions
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26
drivers/media/i2c/ccs/ccs-core.c
View File

@@ -1354,8 +1354,10 @@ static int ccs_change_cci_addr(struct ccs_sensor *sensor)
client->addr = sensor->hwcfg.i2c_addr_dfl;
rval = ccs_write(sensor, CCI_ADDRESS_CTRL,
sensor->hwcfg.i2c_addr_alt << 1);
rval = read_poll_timeout(ccs_write, rval, !rval, CCS_RESET_DELAY_US,
CCS_RESET_TIMEOUT_US, false, sensor,
CCI_ADDRESS_CTRL,
sensor->hwcfg.i2c_addr_alt << 1);
if (rval)
return rval;
@@ -1575,27 +1577,25 @@ static int ccs_power_on(struct device *dev)
if (ccsdev->flags & CCS_DEVICE_FLAG_IS_SMIA)
sleep = SMIAPP_RESET_DELAY(sensor->hwcfg.ext_clk);
else
sleep = 5000;
sleep = CCS_RESET_DELAY_US;
usleep_range(sleep, sleep);
}
/*
* Failures to respond to the address change command have been noticed.
* Those failures seem to be caused by the sensor requiring a longer
* boot time than advertised. An additional 10ms delay seems to work
* around the issue, but the SMIA++ I2C write retry hack makes the delay
* unnecessary. The failures need to be investigated to find a proper
* fix, and a delay will likely need to be added here if the I2C write
* retry hack is reverted before the root cause of the boot time issue
* is found.
* Some devices take longer than the spec-defined time to respond
* after reset. Try until some time has passed before flagging it
* an error.
*/
if (!sensor->reset && !sensor->xshutdown) {
u8 retry = 100;
u32 reset;
rval = ccs_write(sensor, SOFTWARE_RESET, CCS_SOFTWARE_RESET_ON);
rval = read_poll_timeout(ccs_write, rval, !rval,
CCS_RESET_DELAY_US,
CCS_RESET_TIMEOUT_US,
false, sensor, SOFTWARE_RESET,
CCS_SOFTWARE_RESET_ON);
if (rval < 0) {
dev_err(dev, "software reset failed\n");
goto out_cci_addr_fail;

2
drivers/media/i2c/ccs/ccs.h
View File

@@ -43,6 +43,8 @@
#define SMIAPP_RESET_DELAY(clk) \
(1000 + (SMIAPP_RESET_DELAY_CLOCKS * 1000 \
+ (clk) / 1000 - 1) / ((clk) / 1000))
#define CCS_RESET_DELAY_US 5000
#define CCS_RESET_TIMEOUT_US 1000000
#define CCS_COLOUR_COMPONENTS 4