[PATCH v3 1/2][media] Add code to enable/disable ISI_MCK clock.

From: Josh Wu
Date: Thu Sep 22 2011 - 00:14:05 EST


This patch add code to enable/disable ISI_MCK clock when add/remove soc camera device.it also set ISI_MCK frequence before using it.

Signed-off-by: Josh Wu <josh.wu@xxxxxxxxx>
---
drivers/media/video/atmel-isi.c | 30 ++++++++++++++++++++++++++++--
include/media/atmel-isi.h | 2 ++
2 files changed, 30 insertions(+), 2 deletions(-)

diff --git a/drivers/media/video/atmel-isi.c b/drivers/media/video/atmel-isi.c
index 7b89f00..888234a 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 Programmable clock */
+ struct clk *mck;
unsigned int irq;

struct isi_platform_data *pdata;
@@ -763,6 +766,12 @@ static int isi_camera_add_device(struct soc_camera_device *icd)
if (ret)
return ret;

+ ret = clk_enable(isi->mck);
+ if (ret) {
+ clk_disable(isi->pclk);
+ return ret;
+ }
+
isi->icd = icd;
dev_dbg(icd->parent, "Atmel ISI Camera driver attached to camera %d\n",
icd->devnum);
@@ -776,6 +785,7 @@ 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;

@@ -897,6 +907,7 @@ 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 +926,7 @@ 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) {
dev_err(&pdev->dev,
"No config available for Atmel ISI\n");
return -EINVAL;
@@ -944,6 +955,19 @@ static int __devinit atmel_isi_probe(struct platform_device *pdev)
INIT_LIST_HEAD(&isi->video_buffer_list);
INIT_LIST_HEAD(&isi->dma_desc_head);

+ /* Get ISI_MCK, which is provided by Programmable clock */
+ isi->mck = clk_get(dev, "isi_mck");
+ if (IS_ERR(isi->mck)) {
+ dev_err(dev, "Failed to get isi_mck\n");
+ ret = PTR_ERR(isi->mck);
+ goto err_alloc_descriptors;
+ }
+
+ /* Set ISI_MCK's frequency, it should be faster than pixel clock */
+ ret = clk_set_rate(isi->mck, pdata->isi_mck_hz);
+ if (ret < 0)
+ goto err_set_mck_rate;
+
isi->p_fb_descriptors = dma_alloc_coherent(&pdev->dev,
sizeof(struct fbd) * MAX_BUFFER_NUM,
&isi->fb_descriptors_phys,
@@ -951,7 +975,7 @@ static int __devinit atmel_isi_probe(struct platform_device *pdev)
if (!isi->p_fb_descriptors) {
ret = -ENOMEM;
dev_err(&pdev->dev, "Can't allocate descriptors!\n");
- goto err_alloc_descriptors;
+ goto err_set_mck_rate;
}

for (i = 0; i < MAX_BUFFER_NUM; i++) {
@@ -1013,6 +1037,8 @@ err_alloc_ctx:
sizeof(struct fbd) * MAX_BUFFER_NUM,
isi->p_fb_descriptors,
isi->fb_descriptors_phys);
+err_set_mck_rate:
+ clk_put(isi->mck);
err_alloc_descriptors:
kfree(isi);
err_alloc_isi:
diff --git a/include/media/atmel-isi.h b/include/media/atmel-isi.h
index 26cece5..a0229a6 100644
--- a/include/media/atmel-isi.h
+++ b/include/media/atmel-isi.h
@@ -114,6 +114,8 @@ struct isi_platform_data {
u32 data_width_flags;
/* Using for ISI_CFG1 */
u32 frate;
+ /* Using for ISI_MCK, provided by Programmable clock */
+ u32 isi_mck_hz;
};

#endif /* __ATMEL_ISI_H__ */
--
1.6.3.3

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