diff options
| author | Sylwester Nawrocki <s.nawrocki@samsung.com> | 2013-10-29 20:51:04 +0100 |
|---|---|---|
| committer | Sylwester Nawrocki <s.nawrocki@samsung.com> | 2013-12-04 17:19:25 +0100 |
| commit | 4eadfc38c4d6e30775d3764f9a1a3098789d2acc (patch) | |
| tree | a84b8471f7a311a1a5c3bfe19c116bb783ebf5ab /drivers/media/platform | |
| parent | 1d9438f7b560862fd0832355b4ad199b30e67478 (diff) | |
omap3isp: Modify clocks registration to avoid circular references
The clock core code is going to be modified so clk_get() takes
reference on the clock provider module. Until the potential circular
reference issue is properly addressed, we pass NULL as the first
argument to clk_register(), in order to disallow sub-devices taking
a reference on the ISP module back trough clk_get(). This should
prevent locking the modules in memory.
Signed-off-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Diffstat (limited to 'drivers/media/platform')
| -rw-r--r-- | drivers/media/platform/omap3isp/isp.c | 22 | ||||
| -rw-r--r-- | drivers/media/platform/omap3isp/isp.h | 1 |
2 files changed, 17 insertions, 6 deletions
diff --git a/drivers/media/platform/omap3isp/isp.c b/drivers/media/platform/omap3isp/isp.c index 1c3608039663..59106623e71e 100644 --- a/drivers/media/platform/omap3isp/isp.c +++ b/drivers/media/platform/omap3isp/isp.c @@ -290,9 +290,11 @@ static int isp_xclk_init(struct isp_device *isp) struct clk_init_data init; unsigned int i; + for (i = 0; i < ARRAY_SIZE(isp->xclks); ++i) + isp->xclks[i].clk = ERR_PTR(-EINVAL); + for (i = 0; i < ARRAY_SIZE(isp->xclks); ++i) { struct isp_xclk *xclk = &isp->xclks[i]; - struct clk *clk; xclk->isp = isp; xclk->id = i == 0 ? ISP_XCLK_A : ISP_XCLK_B; @@ -305,10 +307,15 @@ static int isp_xclk_init(struct isp_device *isp) init.num_parents = 1; xclk->hw.init = &init; - - clk = devm_clk_register(isp->dev, &xclk->hw); - if (IS_ERR(clk)) - return PTR_ERR(clk); + /* + * The first argument is NULL in order to avoid circular + * reference, as this driver takes reference on the + * sensor subdevice modules and the sensors would take + * reference on this module through clk_get(). + */ + xclk->clk = clk_register(NULL, &xclk->hw); + if (IS_ERR(xclk->clk)) + return PTR_ERR(xclk->clk); if (pdata->xclks[i].con_id == NULL && pdata->xclks[i].dev_id == NULL) @@ -320,7 +327,7 @@ static int isp_xclk_init(struct isp_device *isp) xclk->lookup->con_id = pdata->xclks[i].con_id; xclk->lookup->dev_id = pdata->xclks[i].dev_id; - xclk->lookup->clk = clk; + xclk->lookup->clk = xclk->clk; clkdev_add(xclk->lookup); } @@ -335,6 +342,9 @@ static void isp_xclk_cleanup(struct isp_device *isp) for (i = 0; i < ARRAY_SIZE(isp->xclks); ++i) { struct isp_xclk *xclk = &isp->xclks[i]; + if (!IS_ERR(xclk->clk)) + clk_unregister(xclk->clk); + if (xclk->lookup) clkdev_drop(xclk->lookup); } diff --git a/drivers/media/platform/omap3isp/isp.h b/drivers/media/platform/omap3isp/isp.h index ce65d3ae1aa7..d1e857e41731 100644 --- a/drivers/media/platform/omap3isp/isp.h +++ b/drivers/media/platform/omap3isp/isp.h @@ -135,6 +135,7 @@ struct isp_xclk { struct isp_device *isp; struct clk_hw hw; struct clk_lookup *lookup; + struct clk *clk; enum isp_xclk_id id; spinlock_t lock; /* Protects enabled and divider */ |