diff mbox

[media] at91: add code to initialize and manage the ISI_MCK for Atmel ISI driver.

Message ID 1315218593-10822-1-git-send-email-josh.wu@atmel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Josh Wu Sept. 5, 2011, 10:29 a.m. UTC 
This patch enable the configuration for ISI_MCK, which is provided by programmable clock.

Signed-off-by: Josh Wu <josh.wu@atmel.com>
---
 drivers/media/video/atmel-isi.c |   56 ++++++++++++++++++++++++++++++++++++++-
 include/media/atmel-isi.h       |    4 +++
 2 files changed, 59 insertions(+), 1 deletions(-)

Comments

Russell King - ARM Linux Sept. 5, 2011, 10:33 a.m. UTC | #1 
On Mon, Sep 05, 2011 at 06:29:53PM +0800, Josh Wu wrote:
> +static int initialize_mck(struct atmel_isi *isi,
> +			struct isi_platform_data *pdata)
> +{
> +	int ret;
> +	struct clk *pck_parent;
> +
> +	if (!strlen(pdata->pck_name) || !strlen(pdata->pck_parent_name))
> +		return -EINVAL;
> +
> +	/* ISI_MCK is provided by PCK clock */
> +	isi->mck = clk_get(NULL, pdata->pck_name);

No, this is not how you use the clk API.  You do not pass clock names via
platform data.

You pass clk_get() the struct device.  You then pass clk_get() a
_connection id_ on that _device_ if you have more than one struct clk
associated with the _device_.  You then use clkdev to associate the
struct device plus the connection id with the appropriate struct clk.
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Josh Wu Sept. 6, 2011, 3:29 a.m. UTC | #2 
Hi, Russell

On 09/05/2011 6:34 PM Russell King wrote:

> On Mon, Sep 05, 2011 at 06:29:53PM +0800, Josh Wu wrote:
>> +static int initialize_mck(struct atmel_isi *isi,
>> +			struct isi_platform_data *pdata)
>> +{
>> +	int ret;
>> +	struct clk *pck_parent;
>> +
>> +	if (!strlen(pdata->pck_name) || !strlen(pdata->pck_parent_name))
>> +		return -EINVAL;
>> +
>> +	/* ISI_MCK is provided by PCK clock */
>> +	isi->mck = clk_get(NULL, pdata->pck_name);

> No, this is not how you use the clk API.  You do not pass clock names via
> platform data.

> You pass clk_get() the struct device.  You then pass clk_get() a
> _connection id_ on that _device_ if you have more than one struct clk
> associated with the _device_.  You then use clkdev to associate the
> struct device plus the connection id with the appropriate struct clk.

I think I missed the struct device when called clk_get(). I will fix it in v2 version.

Best Regards,
Josh Wu
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diff mbox

Patch

diff --git a/drivers/media/video/atmel-isi.c b/drivers/media/video/atmel-isi.c
index 7b89f00..8bb59a8 100644
--- a/drivers/media/video/atmel-isi.c
+++ b/drivers/media/video/atmel-isi.c
@@ -90,7 +90,10 @@  struct atmel_isi {
 	struct isi_dma_desc		dma_desc[MAX_BUFFER_NUM];
 
 	struct completion		complete;
+	/* ISI peripherial clock */
 	struct clk			*pclk;
+	/* ISI_MCK, provided by PCK */
+	struct clk			*mck;
 	unsigned int			irq;
 
 	struct isi_platform_data	*pdata;
@@ -763,6 +766,10 @@  static int isi_camera_add_device(struct soc_camera_device *icd)
 	if (ret)
 		return ret;
 
+	ret = clk_enable(isi->mck);
+	if (ret)
+		return ret;
+
 	isi->icd = icd;
 	dev_dbg(icd->parent, "Atmel ISI Camera driver attached to camera %d\n",
 		 icd->devnum);
@@ -776,6 +783,7 @@  static void isi_camera_remove_device(struct soc_camera_device *icd)
 
 	BUG_ON(icd != isi->icd);
 
+	clk_disable(isi->mck);
 	clk_disable(isi->pclk);
 	isi->icd = NULL;
 
@@ -882,6 +890,46 @@  static struct soc_camera_host_ops isi_soc_camera_host_ops = {
 };
 
 /* -----------------------------------------------------------------------*/
+static int initialize_mck(struct atmel_isi *isi,
+			struct isi_platform_data *pdata)
+{
+	int ret;
+	struct clk *pck_parent;
+
+	if (!strlen(pdata->pck_name) || !strlen(pdata->pck_parent_name))
+		return -EINVAL;
+
+	/* ISI_MCK is provided by PCK clock */
+	isi->mck = clk_get(NULL, pdata->pck_name);
+	if (IS_ERR(isi->mck)) {
+		printk(KERN_ERR "Failed to get PCK: %s\n", pdata->pck_name);
+		return PTR_ERR(isi->mck);
+	}
+
+	pck_parent = clk_get(NULL, pdata->pck_parent_name);
+	if (IS_ERR(pck_parent)) {
+		ret = PTR_ERR(pck_parent);
+		printk(KERN_ERR "Failed to get PCK parent: %s\n",
+				pdata->pck_parent_name);
+		goto err_init_mck;
+	}
+
+	ret = clk_set_parent(isi->mck, pck_parent);
+	clk_put(pck_parent);
+	if (ret)
+		goto err_init_mck;
+
+	ret = clk_set_rate(isi->mck, pdata->isi_mck_hz);
+	if (ret < 0)
+		goto err_init_mck;
+
+	return 0;
+
+err_init_mck:
+	clk_put(isi->mck);
+	return ret;
+}
+
 static int __devexit atmel_isi_remove(struct platform_device *pdev)
 {
 	struct soc_camera_host *soc_host = to_soc_camera_host(&pdev->dev);
@@ -897,6 +945,7 @@  static int __devexit atmel_isi_remove(struct platform_device *pdev)
 			isi->fb_descriptors_phys);
 
 	iounmap(isi->regs);
+	clk_put(isi->mck);
 	clk_put(isi->pclk);
 	kfree(isi);
 
@@ -915,7 +964,8 @@  static int __devinit atmel_isi_probe(struct platform_device *pdev)
 	struct isi_platform_data *pdata;
 
 	pdata = dev->platform_data;
-	if (!pdata || !pdata->data_width_flags) {
+	if (!pdata || !pdata->data_width_flags || !pdata->isi_mck_hz
+			|| !pdata->pck_name || !pdata->pck_parent_name) {
 		dev_err(&pdev->dev,
 			"No config available for Atmel ISI\n");
 		return -EINVAL;
@@ -944,6 +994,10 @@  static int __devinit atmel_isi_probe(struct platform_device *pdev)
 	INIT_LIST_HEAD(&isi->video_buffer_list);
 	INIT_LIST_HEAD(&isi->dma_desc_head);
 
+	ret = initialize_mck(isi, pdata);
+	if (ret)
+		goto err_alloc_descriptors;
+
 	isi->p_fb_descriptors = dma_alloc_coherent(&pdev->dev,
 				sizeof(struct fbd) * MAX_BUFFER_NUM,
 				&isi->fb_descriptors_phys,
diff --git a/include/media/atmel-isi.h b/include/media/atmel-isi.h
index 26cece5..dcbb822 100644
--- a/include/media/atmel-isi.h
+++ b/include/media/atmel-isi.h
@@ -114,6 +114,10 @@  struct isi_platform_data {
 	u32 data_width_flags;
 	/* Using for ISI_CFG1 */
 	u32 frate;
+	/* Using for ISI_MCK, provided by PCK */
+	u32 isi_mck_hz;
+	const char *pck_name;
+	const char *pck_parent_name;
 };
 
 #endif /* __ATMEL_ISI_H__ */