diff options
| author | Frank Schaefer <fschaefer.oss@googlemail.com> | 2017-02-19 15:29:17 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@s-opensource.com> | 2017-03-22 11:38:38 -0300 |
| commit | 9e00695364fb74f3aa9912a6a686db8446dcd695 (patch) | |
| tree | 3e7c30d01ccda5064ad56f22ebfd41afe1c615df /drivers/media/usb | |
| parent | 3b8b2e1cea78652ecf7b976a68f87220a3f27b28 (diff) | |
| download | blackbird-op-linux-9e00695364fb74f3aa9912a6a686db8446dcd695.tar.gz blackbird-op-linux-9e00695364fb74f3aa9912a6a686db8446dcd695.zip | |
[media] em28xx: reduce stack usage in sensor probing functions
It's no longer necessary to keep the i2c_client in the device struct
unmodified until a sensor is found, so reduce stack usage in
em28xx_probe_sensor_micron() and em28xx_probe_sensor_omnivision() by using
a pointer to the client instead of a local copy.
Reported-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Frank Schäfer <fschaefer.oss@googlemail.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media/usb')
| -rw-r--r-- | drivers/media/usb/em28xx/em28xx-camera.c | 42 |
1 files changed, 20 insertions, 22 deletions
diff --git a/drivers/media/usb/em28xx/em28xx-camera.c b/drivers/media/usb/em28xx/em28xx-camera.c index 89c890ba7dd6..7b4129ab1cf9 100644 --- a/drivers/media/usb/em28xx/em28xx-camera.c +++ b/drivers/media/usb/em28xx/em28xx-camera.c @@ -110,44 +110,44 @@ static int em28xx_probe_sensor_micron(struct em28xx *dev) __be16 id_be; u16 id; - struct i2c_client client = dev->i2c_client[dev->def_i2c_bus]; + struct i2c_client *client = &dev->i2c_client[dev->def_i2c_bus]; dev->em28xx_sensor = EM28XX_NOSENSOR; for (i = 0; micron_sensor_addrs[i] != I2C_CLIENT_END; i++) { - client.addr = micron_sensor_addrs[i]; + client->addr = micron_sensor_addrs[i]; /* NOTE: i2c_smbus_read_word_data() doesn't work with BE data */ /* Read chip ID from register 0x00 */ reg = 0x00; - ret = i2c_master_send(&client, ®, 1); + ret = i2c_master_send(client, ®, 1); if (ret < 0) { if (ret != -ENXIO) dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } - ret = i2c_master_recv(&client, (u8 *)&id_be, 2); + ret = i2c_master_recv(client, (u8 *)&id_be, 2); if (ret < 0) { dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } id = be16_to_cpu(id_be); /* Read chip ID from register 0xff */ reg = 0xff; - ret = i2c_master_send(&client, ®, 1); + ret = i2c_master_send(client, ®, 1); if (ret < 0) { dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } - ret = i2c_master_recv(&client, (u8 *)&id_be, 2); + ret = i2c_master_recv(client, (u8 *)&id_be, 2); if (ret < 0) { dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } /* Validate chip ID to be sure we have a Micron device */ @@ -197,7 +197,6 @@ static int em28xx_probe_sensor_micron(struct em28xx *dev) dev_info(&dev->intf->dev, "sensor %s detected\n", name); - dev->i2c_client[dev->def_i2c_bus].addr = client.addr; return 0; } @@ -213,30 +212,30 @@ static int em28xx_probe_sensor_omnivision(struct em28xx *dev) char *name; u8 reg; u16 id; - struct i2c_client client = dev->i2c_client[dev->def_i2c_bus]; + struct i2c_client *client = &dev->i2c_client[dev->def_i2c_bus]; dev->em28xx_sensor = EM28XX_NOSENSOR; /* NOTE: these devices have the register auto incrementation disabled * by default, so we have to use single byte reads ! */ for (i = 0; omnivision_sensor_addrs[i] != I2C_CLIENT_END; i++) { - client.addr = omnivision_sensor_addrs[i]; + client->addr = omnivision_sensor_addrs[i]; /* Read manufacturer ID from registers 0x1c-0x1d (BE) */ reg = 0x1c; - ret = i2c_smbus_read_byte_data(&client, reg); + ret = i2c_smbus_read_byte_data(client, reg); if (ret < 0) { if (ret != -ENXIO) dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } id = ret << 8; reg = 0x1d; - ret = i2c_smbus_read_byte_data(&client, reg); + ret = i2c_smbus_read_byte_data(client, reg); if (ret < 0) { dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } id += ret; @@ -245,20 +244,20 @@ static int em28xx_probe_sensor_omnivision(struct em28xx *dev) continue; /* Read product ID from registers 0x0a-0x0b (BE) */ reg = 0x0a; - ret = i2c_smbus_read_byte_data(&client, reg); + ret = i2c_smbus_read_byte_data(client, reg); if (ret < 0) { dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } id = ret << 8; reg = 0x0b; - ret = i2c_smbus_read_byte_data(&client, reg); + ret = i2c_smbus_read_byte_data(client, reg); if (ret < 0) { dev_err(&dev->intf->dev, "couldn't read from i2c device 0x%02x: error %i\n", - client.addr << 1, ret); + client->addr << 1, ret); continue; } id += ret; @@ -309,7 +308,6 @@ static int em28xx_probe_sensor_omnivision(struct em28xx *dev) dev_info(&dev->intf->dev, "sensor %s detected\n", name); - dev->i2c_client[dev->def_i2c_bus].addr = client.addr; return 0; } |
