Commit 4d5123a0 authored by Shawn Lin's avatar Shawn Lin Committed by Greg Kroah-Hartman

mmc: dw_mmc: Avoid accessing registers in runtime suspended state

commit 5b43df8b 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: e9ed8835 ("mmc: dw_mmc: add runtime PM callback")
Cc: <stable@vger.kernel.org>
Signed-off-by: default avatarShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: default avatarJaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: default avatarUlf Hansson <ulf.hansson@linaro.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent cb65fc21
......@@ -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;
}
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment