diff options
| author | Jonathan Corbet <corbet@lwn.net> | 2007-05-22 00:37:58 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <mchehab@infradead.org> | 2007-05-22 16:16:27 -0300 |
| commit | 7acf90c70c6ee063f7465b2f10e2083bc49f355b (patch) | |
| tree | 6b00a98e964864b400ec03dc52598cb5aa0c1ea7 /drivers | |
| parent | 82c01d3d5a26f82aea1fb2e9a357dfb6404f44db (diff) | |
| download | lwn-7acf90c70c6ee063f7465b2f10e2083bc49f355b.tar.gz lwn-7acf90c70c6ee063f7465b2f10e2083bc49f355b.zip | |
V4L/DVB (5690): Cafe_ccic: Properly power down the sensor
The proper method for powering down the sensor on OLPC systems has
changed somewhat; in particular, the sensor must be powered down
completely (rather than simply told to power down) or the associated
"camera active" LED will stay on.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/media/video/cafe_ccic-regs.h | 6 | ||||
| -rw-r--r-- | drivers/media/video/cafe_ccic.c | 18 |
2 files changed, 23 insertions, 1 deletions
diff --git a/drivers/media/video/cafe_ccic-regs.h b/drivers/media/video/cafe_ccic-regs.h index b2c22a0d6643..8e2a87cdc791 100644 --- a/drivers/media/video/cafe_ccic-regs.h +++ b/drivers/media/video/cafe_ccic-regs.h @@ -150,6 +150,12 @@ #define REG_GL_IMASK 0x300c /* Interrupt mask register */ #define GIMSK_CCIC_EN 0x00000004 /* CCIC Interrupt enable */ +#define REG_GL_FCR 0x3038 /* GPIO functional control register */ +#define GFCR_GPIO_ON 0x08 /* Camera GPIO enabled */ +#define REG_GL_GPIOR 0x315c /* GPIO register */ +#define GGPIO_OUT 0x80000 /* GPIO output */ +#define GGPIO_VAL 0x00008 /* Output pin value */ + #define REG_LEN REG_GL_IMASK + 4 diff --git a/drivers/media/video/cafe_ccic.c b/drivers/media/video/cafe_ccic.c index 96254dbaf625..c08f650df423 100644 --- a/drivers/media/video/cafe_ccic.c +++ b/drivers/media/video/cafe_ccic.c @@ -775,6 +775,12 @@ static void cafe_ctlr_power_up(struct cafe_camera *cam) spin_lock_irqsave(&cam->dev_lock, flags); cafe_reg_clear_bit(cam, REG_CTRL1, C1_PWRDWN); /* + * Part one of the sensor dance: turn the global + * GPIO signal on. + */ + cafe_reg_write(cam, REG_GL_FCR, GFCR_GPIO_ON); + cafe_reg_write(cam, REG_GL_GPIOR, GGPIO_OUT|GGPIO_VAL); + /* * Put the sensor into operational mode (assumes OLPC-style * wiring). Control 0 is reset - set to 1 to operate. * Control 1 is power down, set to 0 to operate. @@ -784,6 +790,7 @@ static void cafe_ctlr_power_up(struct cafe_camera *cam) cafe_reg_write(cam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C0); // mdelay(1); /* Enough? */ spin_unlock_irqrestore(&cam->dev_lock, flags); + msleep(5); /* Just to be sure */ } static void cafe_ctlr_power_down(struct cafe_camera *cam) @@ -792,6 +799,8 @@ static void cafe_ctlr_power_down(struct cafe_camera *cam) spin_lock_irqsave(&cam->dev_lock, flags); cafe_reg_write(cam, REG_GPR, GPR_C1EN|GPR_C0EN|GPR_C1); + cafe_reg_write(cam, REG_GL_FCR, GFCR_GPIO_ON); + cafe_reg_write(cam, REG_GL_GPIOR, GGPIO_OUT); cafe_reg_set_bit(cam, REG_CTRL1, C1_PWRDWN); spin_unlock_irqrestore(&cam->dev_lock, flags); } @@ -851,6 +860,7 @@ static int cafe_cam_init(struct cafe_camera *cam) ret = 0; cam->state = S_IDLE; out: + cafe_ctlr_power_down(cam); mutex_unlock(&cam->s_mutex); return ret; } @@ -2103,10 +2113,16 @@ static int cafe_pci_probe(struct pci_dev *pdev, ret = request_irq(pdev->irq, cafe_irq, IRQF_SHARED, "cafe-ccic", cam); if (ret) goto out_iounmap; + /* + * Initialize the controller and leave it powered up. It will + * stay that way until the sensor driver shows up. + */ cafe_ctlr_init(cam); cafe_ctlr_power_up(cam); /* - * Set up I2C/SMBUS communications + * Set up I2C/SMBUS communications. We have to drop the mutex here + * because the sensor could attach in this call chain, leading to + * unsightly deadlocks. */ mutex_unlock(&cam->s_mutex); /* attach can deadlock */ ret = cafe_smbus_setup(cam); |