[PATCH v2 2/2] [media]: mx2_camera: Fix regression caused by clock conversion
javier Martin
javier.martin at vista-silicon.com
Tue Oct 9 07:16:22 EDT 2012
On 9 October 2012 00:37, Fabio Estevam <festevam at gmail.com> wrote:
> From: Fabio Estevam <fabio.estevam at freescale.com>
>
> Since mx27 transitioned to the commmon clock framework in 3.5, the correct way
> to acquire the csi clock is to get csi_ahb and csi_per clocks separately.
>
> By not doing so the camera sensor does not probe correctly:
>
> soc-camera-pdrv soc-camera-pdrv.0: Probing soc-camera-pdrv.0
> mx2-camera mx2-camera.0: Camera driver attached to camera 0
> ov2640 0-0030: Product ID error fb:fb
> mx2-camera mx2-camera.0: Camera driver detached from camera 0
> mx2-camera mx2-camera.0: MX2 Camera (CSI) driver probed, clock frequency: 66500000
>
> Adapt the mx2_camera driver to the new clock framework and make it functional
> again.
>
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> ---
> Changes since v1:
> - Rebased against linux-next 20121008.
>
> drivers/media/platform/soc_camera/mx2_camera.c | 47 +++++++++++++++++-------
> 1 file changed, 34 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/media/platform/soc_camera/mx2_camera.c b/drivers/media/platform/soc_camera/mx2_camera.c
> index 403d7f1..9f8c5f0 100644
> --- a/drivers/media/platform/soc_camera/mx2_camera.c
> +++ b/drivers/media/platform/soc_camera/mx2_camera.c
> @@ -272,7 +272,8 @@ struct mx2_camera_dev {
> struct device *dev;
> struct soc_camera_host soc_host;
> struct soc_camera_device *icd;
> - struct clk *clk_csi, *clk_emma_ahb, *clk_emma_ipg;
> + struct clk *clk_emma_ahb, *clk_emma_ipg;
> + struct clk *clk_csi_ahb, *clk_csi_per;
>
> void __iomem *base_csi, *base_emma;
>
> @@ -432,7 +433,8 @@ static void mx2_camera_deactivate(struct mx2_camera_dev *pcdev)
> {
> unsigned long flags;
>
> - clk_disable_unprepare(pcdev->clk_csi);
> + clk_disable_unprepare(pcdev->clk_csi_ahb);
> + clk_disable_unprepare(pcdev->clk_csi_per);
> writel(0, pcdev->base_csi + CSICR1);
> if (cpu_is_mx27()) {
> writel(0, pcdev->base_emma + PRP_CNTL);
> @@ -460,7 +462,11 @@ static int mx2_camera_add_device(struct soc_camera_device *icd)
> if (pcdev->icd)
> return -EBUSY;
>
> - ret = clk_prepare_enable(pcdev->clk_csi);
> + ret = clk_prepare_enable(pcdev->clk_csi_ahb);
> + if (ret < 0)
> + return ret;
> +
> + ret = clk_prepare_enable(pcdev->clk_csi_per);
> if (ret < 0)
> return ret;
>
> @@ -1725,11 +1731,18 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
> goto exit;
> }
>
> - pcdev->clk_csi = devm_clk_get(&pdev->dev, "ahb");
> - if (IS_ERR(pcdev->clk_csi)) {
> - dev_err(&pdev->dev, "Could not get csi clock\n");
> - err = PTR_ERR(pcdev->clk_csi);
> - goto exit;
> + pcdev->clk_csi_ahb = devm_clk_get(&pdev->dev, "ahb");
> + if (IS_ERR(pcdev->clk_csi_ahb)) {
> + dev_err(&pdev->dev, "Could not get csi ahb clock\n");
> + err = PTR_ERR(pcdev->clk_csi_ahb);
> + goto exit;
> + }
> +
> + pcdev->clk_csi_per = devm_clk_get(&pdev->dev, "per");
> + if (IS_ERR(pcdev->clk_csi_per)) {
> + dev_err(&pdev->dev, "Could not get csi per clock\n");
> + err = PTR_ERR(pcdev->clk_csi_per);
> + goto exit_csi_ahb;
> }
>
> pcdev->pdata = pdev->dev.platform_data;
> @@ -1738,14 +1751,15 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
>
> pcdev->platform_flags = pcdev->pdata->flags;
>
> - rate = clk_round_rate(pcdev->clk_csi, pcdev->pdata->clk * 2);
> + rate = clk_round_rate(pcdev->clk_csi_per,
> + pcdev->pdata->clk * 2);
> if (rate <= 0) {
> err = -ENODEV;
> - goto exit;
> + goto exit_csi_per;
> }
> - err = clk_set_rate(pcdev->clk_csi, rate);
> + err = clk_set_rate(pcdev->clk_csi_per, rate);
> if (err < 0)
> - goto exit;
> + goto exit_csi_per;
> }
>
> INIT_LIST_HEAD(&pcdev->capture);
> @@ -1801,7 +1815,7 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
> goto exit_free_emma;
>
> dev_info(&pdev->dev, "MX2 Camera (CSI) driver probed, clock frequency: %ld\n",
> - clk_get_rate(pcdev->clk_csi));
> + clk_get_rate(pcdev->clk_csi_per));
>
> return 0;
>
> @@ -1812,6 +1826,10 @@ eallocctx:
> clk_disable_unprepare(pcdev->clk_emma_ipg);
> clk_disable_unprepare(pcdev->clk_emma_ahb);
> }
> +exit_csi_per:
> + clk_disable_unprepare(pcdev->clk_csi_per);
> +exit_csi_ahb:
> + clk_disable_unprepare(pcdev->clk_csi_ahb);
> exit:
> return err;
> }
> @@ -1831,6 +1849,9 @@ static int __devexit mx2_camera_remove(struct platform_device *pdev)
> clk_disable_unprepare(pcdev->clk_emma_ahb);
> }
>
> + clk_disable_unprepare(pcdev->clk_csi_per);
> + clk_disable_unprepare(pcdev->clk_csi_ahb);
> +
> dev_info(&pdev->dev, "MX2 Camera driver unloaded\n");
>
> return 0;
> --
> 1.7.9.5
>
This patch doesn't fix the BUG it claims to, since I have it working
properly in our Visstrim M10 platform without it. Look:
soc-camera-pdrv soc-camera-pdrv.0: Probing soc-camera-pdrv.0
mx2-camera mx2-camera.0: Camera driver attached to camera 0
ov7670 0-0021: chip found @ 0x42 (imx-i2c)
[..]
mx2-camera mx2-camera.0: Camera driver detached from camera 0
mx2-camera mx2-camera.0: MX2 Camera (CSI) driver probed, clock
frequency: 66500000
Furthermore, it's not correct, since there isn't such "per" clock for
the CSI in 3.5 [1], 3.6 [2], linux-next-20121008[3], or
next-20121009[4].
[1] http://lxr.linux.no/#linux+v3.5/arch/arm/mach-imx/clk-imx27.c#L226
[2] http://lxr.linux.no/#linux+v3.6/arch/arm/mach-imx/clk-imx27.c#L226
[3] http://git.kernel.org/?p=linux/kernel/git/next/linux-next.git;a=blob;f=arch/arm/mach-imx/clk-imx27.c;h=3b6b640eed247ea1b7848c7a7fa01801f0190cde;hb=cc925138a0dd9ae388135bb3cf11ee1729f9c4e9#l226
[4] http://git.kernel.org/?p=linux/kernel/git/next/linux-next.git;a=blob;f=arch/arm/mach-imx/clk-imx27.c;h=3b6b640eed247ea1b7848c7a7fa01801f0190cde;hb=b066f61482c7eac44e656499426a3c56d29c32ed#l226
Regards.
--
Javier Martin
Vista Silicon S.L.
CDTUC - FASE C - Oficina S-345
Avda de los Castros s/n
39005- Santander. Cantabria. Spain
+34 942 25 32 60
www.vista-silicon.com
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