Smatch reports: drivers/gpu/drm/sun4i/sun4i_tcon.c:805 sun4i_tcon_init_clocks() warn: 'tcon->clk' from clk_prepare_enable() not released on lines: 792,801. In the function sun4i_tcon_init_clocks(), tcon->clk and tcon->sclk0 are not disabled in the error handling, which affects the release of these variable. Although sun4i_tcon_bind(), which calls sun4i_tcon_init_clocks(), use sun4i_tcon_free_clocks to disable the variables mentioned, but the error handling branch of sun4i_tcon_init_clocks() ignores the required disable process. To fix this issue, use the devm_clk_get_enabled to automatically balance enable and disabled calls. As original implementation use sun4i_tcon_free_clocks() to disable clk explicitly, we delete the related calls and error handling that are no longer needed. Fixes: 9026e0d122ac ("drm: Add Allwinner A10 Display Engine support") Fixes: b14e945bda8a ("drm/sun4i: tcon: Prepare and enable TCON channel 0 clock at init") Fixes: 8e9240472522 ("drm/sun4i: support TCONs without channel 1") Fixes: 34d698f6e349 ("drm/sun4i: Add has_channel_0 TCON quirk") Signed-off-by: XuDong Liu <m202071377@xxxxxxxxxxx> Reviewed-by: Dongliang Mu <dzm91@xxxxxxxxxxx> --- The issue is discovered by static analysis, and the patch is not tested yet. --- drivers/gpu/drm/sun4i/sun4i_tcon.c | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c index 523a6d787921..936796851ffd 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c @@ -778,21 +778,19 @@ static irqreturn_t sun4i_tcon_handler(int irq, void *private) static int sun4i_tcon_init_clocks(struct device *dev, struct sun4i_tcon *tcon) { - tcon->clk = devm_clk_get(dev, "ahb"); + tcon->clk = devm_clk_get_enabled(dev, "ahb"); if (IS_ERR(tcon->clk)) { dev_err(dev, "Couldn't get the TCON bus clock\n"); return PTR_ERR(tcon->clk); } - clk_prepare_enable(tcon->clk); if (tcon->quirks->has_channel_0) { - tcon->sclk0 = devm_clk_get(dev, "tcon-ch0"); + tcon->sclk0 = devm_clk_get_enabled(dev, "tcon-ch0"); if (IS_ERR(tcon->sclk0)) { dev_err(dev, "Couldn't get the TCON channel 0 clock\n"); return PTR_ERR(tcon->sclk0); } } - clk_prepare_enable(tcon->sclk0); if (tcon->quirks->has_channel_1) { tcon->sclk1 = devm_clk_get(dev, "tcon-ch1"); @@ -805,12 +803,6 @@ static int sun4i_tcon_init_clocks(struct device *dev, return 0; } -static void sun4i_tcon_free_clocks(struct sun4i_tcon *tcon) -{ - clk_disable_unprepare(tcon->sclk0); - clk_disable_unprepare(tcon->clk); -} - static int sun4i_tcon_init_irq(struct device *dev, struct sun4i_tcon *tcon) { @@ -1223,14 +1215,14 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master, ret = sun4i_tcon_init_regmap(dev, tcon); if (ret) { dev_err(dev, "Couldn't init our TCON regmap\n"); - goto err_free_clocks; + goto err_assert_reset; } if (tcon->quirks->has_channel_0) { ret = sun4i_dclk_create(dev, tcon); if (ret) { dev_err(dev, "Couldn't create our TCON dot clock\n"); - goto err_free_clocks; + goto err_assert_reset; } } @@ -1293,8 +1285,6 @@ static int sun4i_tcon_bind(struct device *dev, struct device *master, err_free_dotclock: if (tcon->quirks->has_channel_0) sun4i_dclk_free(tcon); -err_free_clocks: - sun4i_tcon_free_clocks(tcon); err_assert_reset: reset_control_assert(tcon->lcd_rst); return ret; @@ -1308,7 +1298,6 @@ static void sun4i_tcon_unbind(struct device *dev, struct device *master, list_del(&tcon->list); if (tcon->quirks->has_channel_0) sun4i_dclk_free(tcon); - sun4i_tcon_free_clocks(tcon); } static const struct component_ops sun4i_tcon_ops = { -- 2.34.1