4.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Shawn Lin shawn.lin@rock-chips.com
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
--- drivers/mmc/host/dw_mmc.c | 4 ++++ 1 file changed, 4 insertions(+)
--- 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_f { 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_f 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; }