diff options
| author | Shawn Lin <shawn.lin@rock-chips.com> | 2018-02-23 16:47:25 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-03-08 22:41:03 -0800 |
| commit | 4d5123a0b37cab76958bdd7d6d2c26a40ca52e7f (patch) | |
| tree | 3b9129b46ce026d76b94d9fb65963a7482a7c1e7 /drivers/mmc/host/dw_mmc.c | |
| parent | cb65fc21f3877599e1c22710c5fdbefd0be010d4 (diff) | |
mmc: dw_mmc: Avoid accessing registers in runtime suspended state
commit 5b43df8b4c1a7f0c3fbf793c9566068e6b1e570c upstream.
cat /sys/kernel/debug/mmc0/regs will hang up the system since
it's in runtime suspended state, so the genpd and biu_clk is
off. This patch fixes this problem by calling pm_runtime_get_sync
to wake it up before reading the registers.
Fixes: e9ed8835e990 ("mmc: dw_mmc: add runtime PM callback")
Cc: <stable@vger.kernel.org>
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/mmc/host/dw_mmc.c')
| -rw-r--r-- | drivers/mmc/host/dw_mmc.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c index 4f2806720c5c..76b8dec1d30b 100644 --- a/drivers/mmc/host/dw_mmc.c +++ b/drivers/mmc/host/dw_mmc.c @@ -165,6 +165,8 @@ static int dw_mci_regs_show(struct seq_file *s, void *v) { struct dw_mci *host = s->private; + pm_runtime_get_sync(host->dev); + seq_printf(s, "STATUS:\t0x%08x\n", mci_readl(host, STATUS)); seq_printf(s, "RINTSTS:\t0x%08x\n", mci_readl(host, RINTSTS)); seq_printf(s, "CMD:\t0x%08x\n", mci_readl(host, CMD)); @@ -172,6 +174,8 @@ static int dw_mci_regs_show(struct seq_file *s, void *v) seq_printf(s, "INTMASK:\t0x%08x\n", mci_readl(host, INTMASK)); seq_printf(s, "CLKENA:\t0x%08x\n", mci_readl(host, CLKENA)); + pm_runtime_put_autosuspend(host->dev); + return 0; } |