| Message ID | 1513691849-6378-1-git-send-email-baijiaju1990@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi, It's almost good! You have to fix these checkpatch Warning/Check: WARNING: Block comments use a trailing */ on a separate line #36: FILE: drivers/media/platform/sti/bdisp/bdisp-hw.c:383: + * needing any delays */ CHECK: Alignment should match open parenthesis #38: FILE: drivers/media/platform/sti/bdisp/bdisp-hw.c:385: + if (readl_poll_timeout_atomic(bdisp->regs + BLT_STA1, tmp, + (tmp & BLT_STA1_IDLE), POLL_RST_DELAY_MS, From kernel documentation in the "Posting patches" chapter: "You should always run patches through scripts/checkpatch.pl and address the complaints it comes up with." And, please use the --strict option Thanks for your understanding. BR Fabien On 19/12/17 14:57, Jia-Ju Bai wrote: > The driver may sleep under a spinlock. > The function call path is: > bdisp_device_run (acquire the spinlock) > bdisp_hw_reset > msleep --> may sleep > > To fix it, readl_poll_timeout_atomic is used to replace msleep. > > This bug is found by my static analysis tool(DSAC) and > checked by my code review. > > Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> > --- > drivers/media/platform/sti/bdisp/bdisp-hw.c | 23 ++++++++++++----------- > 1 file changed, 12 insertions(+), 11 deletions(-) > > diff --git a/drivers/media/platform/sti/bdisp/bdisp-hw.c b/drivers/media/platform/sti/bdisp/bdisp-hw.c > index b7892f3..b63d9c9 100644 > --- a/drivers/media/platform/sti/bdisp/bdisp-hw.c > +++ b/drivers/media/platform/sti/bdisp/bdisp-hw.c > @@ -4,7 +4,7 @@ > * License terms: GNU General Public License (GPL), version 2 > */ > > -#include <linux/delay.h> > +#include <linux/iopoll.h> > > #include "bdisp.h" > #include "bdisp-filter.h" > @@ -15,7 +15,7 @@ > > /* Reset & boot poll config */ > #define POLL_RST_MAX 50 > -#define POLL_RST_DELAY_MS 20 > +#define POLL_RST_DELAY_US 20000 > > enum bdisp_target_plan { > BDISP_RGB, > @@ -366,7 +366,7 @@ struct bdisp_filter_addr { > */ > int bdisp_hw_reset(struct bdisp_dev *bdisp) > { > - unsigned int i; > + u32 tmp; > > dev_dbg(bdisp->dev, "%s\n", __func__); > > @@ -378,16 +378,17 @@ int bdisp_hw_reset(struct bdisp_dev *bdisp) > bdisp->regs + BLT_CTL); > writel(0, bdisp->regs + BLT_CTL); > > - /* Wait for reset done */ > - for (i = 0; i < POLL_RST_MAX; i++) { > - if (readl(bdisp->regs + BLT_STA1) & BLT_STA1_IDLE) > - break; > - msleep(POLL_RST_DELAY_MS); > - } > - if (i == POLL_RST_MAX) > + /* Wait for reset done. > + * Despite the large timeout, most of the time the reset happens without > + * needing any delays */ shall be + * needing any delays + */ > + if (readl_poll_timeout_atomic(bdisp->regs + BLT_STA1, tmp, > + (tmp & BLT_STA1_IDLE), POLL_RST_DELAY_US, > + POLL_RST_DELAY_US * POLL_RST_MAX)) { shall be: + if (readl_poll_timeout_atomic(bdisp->regs + BLT_STA1, tmp, + tmp & BLT_STA1_IDLE, POLL_RST_DELAY_US, + POLL_RST_DELAY_US * POLL_RST_MAX)) { > dev_err(bdisp->dev, "Reset timeout\n"); > + return -EAGAIN; > + } > > - return (i == POLL_RST_MAX) ? -EAGAIN : 0; > + return 0; > } > > /**
diff --git a/drivers/media/platform/sti/bdisp/bdisp-hw.c b/drivers/media/platform/sti/bdisp/bdisp-hw.c index b7892f3..b63d9c9 100644 --- a/drivers/media/platform/sti/bdisp/bdisp-hw.c +++ b/drivers/media/platform/sti/bdisp/bdisp-hw.c @@ -4,7 +4,7 @@ * License terms: GNU General Public License (GPL), version 2 */ -#include <linux/delay.h> +#include <linux/iopoll.h> #include "bdisp.h" #include "bdisp-filter.h" @@ -15,7 +15,7 @@ /* Reset & boot poll config */ #define POLL_RST_MAX 50 -#define POLL_RST_DELAY_MS 20 +#define POLL_RST_DELAY_US 20000 enum bdisp_target_plan { BDISP_RGB, @@ -366,7 +366,7 @@ struct bdisp_filter_addr { */ int bdisp_hw_reset(struct bdisp_dev *bdisp) { - unsigned int i; + u32 tmp; dev_dbg(bdisp->dev, "%s\n", __func__); @@ -378,16 +378,17 @@ int bdisp_hw_reset(struct bdisp_dev *bdisp) bdisp->regs + BLT_CTL); writel(0, bdisp->regs + BLT_CTL); - /* Wait for reset done */ - for (i = 0; i < POLL_RST_MAX; i++) { - if (readl(bdisp->regs + BLT_STA1) & BLT_STA1_IDLE) - break; - msleep(POLL_RST_DELAY_MS); - } - if (i == POLL_RST_MAX) + /* Wait for reset done. + * Despite the large timeout, most of the time the reset happens without + * needing any delays */ + if (readl_poll_timeout_atomic(bdisp->regs + BLT_STA1, tmp, + (tmp & BLT_STA1_IDLE), POLL_RST_DELAY_US, + POLL_RST_DELAY_US * POLL_RST_MAX)) { dev_err(bdisp->dev, "Reset timeout\n"); + return -EAGAIN; + } - return (i == POLL_RST_MAX) ? -EAGAIN : 0; + return 0; } /**
The driver may sleep under a spinlock. The function call path is: bdisp_device_run (acquire the spinlock) bdisp_hw_reset msleep --> may sleep To fix it, readl_poll_timeout_atomic is used to replace msleep. This bug is found by my static analysis tool(DSAC) and checked by my code review. Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> --- drivers/media/platform/sti/bdisp/bdisp-hw.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-)