From 57822068dd120386b98891cb151dc20107b63ba7 Mon Sep 17 00:00:00 2001 From: Janusz Krzysztofik Date: Sun, 13 Oct 2019 09:50:45 -0300 Subject: [PATCH] media: ov6650: Fix stored frame interval not in sync with hardware The driver stores a frame interval value supposed to be in line with hardware state in a device private structure. Since the driver initial submission, the respective field of the structure has never been initialised on device probe. Moreover, if updated from .s_frame_interval(), a new value is stored before it is applied on hardware. If an error occurs during device update, the stored value may no longer reflect hardware state and consecutive calls to .g_frame_interval() may return incorrect information. Assuming a failed update of the device means its actual state hasn't changed, update the frame interval field of the device private structure with a new value only after it is successfully applied on hardware so it always reflects actual hardware state to the extent possible. Also, initialise the field with hardware default frame interval on device probe. Signed-off-by: Janusz Krzysztofik Signed-off-by: Sakari Ailus Signed-off-by: Mauro Carvalho Chehab --- drivers/media/i2c/ov6650.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/media/i2c/ov6650.c b/drivers/media/i2c/ov6650.c index 16887049f0cd..f60aeb1f7813 100644 --- a/drivers/media/i2c/ov6650.c +++ b/drivers/media/i2c/ov6650.c @@ -130,6 +130,7 @@ #define CLKRC_24MHz 0xc0 #define CLKRC_DIV_MASK 0x3f #define GET_CLKRC_DIV(x) (((x) & CLKRC_DIV_MASK) + 1) +#define DEF_CLKRC 0x00 #define COMA_RESET BIT(7) #define COMA_QCIF BIT(5) @@ -783,19 +784,17 @@ static int ov6650_s_frame_interval(struct v4l2_subdev *sd, else if (div > GET_CLKRC_DIV(CLKRC_DIV_MASK)) div = GET_CLKRC_DIV(CLKRC_DIV_MASK); - /* - * Keep result to be used as tpf limit - * for subsequent clock divider calculations - */ - priv->tpf.numerator = div; - priv->tpf.denominator = FRAME_RATE_MAX; + tpf->numerator = div; + tpf->denominator = FRAME_RATE_MAX; - clkrc = to_clkrc(&priv->tpf, priv->pclk_limit, priv->pclk_max); + clkrc = to_clkrc(tpf, priv->pclk_limit, priv->pclk_max); ret = ov6650_reg_rmw(client, REG_CLKRC, clkrc, CLKRC_DIV_MASK); if (!ret) { - tpf->numerator = GET_CLKRC_DIV(clkrc); - tpf->denominator = FRAME_RATE_MAX; + priv->tpf.numerator = GET_CLKRC_DIV(clkrc); + priv->tpf.denominator = FRAME_RATE_MAX; + + *tpf = priv->tpf; } return ret; @@ -1038,6 +1037,10 @@ static int ov6650_probe(struct i2c_client *client, priv->rect.width = W_CIF; priv->rect.height = H_CIF; + /* Hardware default frame interval */ + priv->tpf.numerator = GET_CLKRC_DIV(DEF_CLKRC); + priv->tpf.denominator = FRAME_RATE_MAX; + priv->subdev.internal_ops = &ov6650_internal_ops; ret = v4l2_async_register_subdev(&priv->subdev);