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Subject[PATCH v3 2/2] phy: rockchip-emmc: use regmap_read_poll_timeout to poll dllrdy
Date
From: Shawn Lin <shawn.lin@rock-chips.com>

Just use the API instead of open-coding it, no functional change
intended.

Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>

---

Changes in v3:
- As Doug commented on https://patchwork.kernel.org/patch/10154797,
Change "1, 50" to "0, 50".

Changes in v2:
- As Brian commented on https://patchwork.kernel.org/patch/10139891/,
changed the note and added to print error value with
regmap_read_poll_timeout API.

drivers/phy/rockchip/phy-rockchip-emmc.c | 33 +++++++++++---------------------
1 file changed, 11 insertions(+), 22 deletions(-)

diff --git a/drivers/phy/rockchip/phy-rockchip-emmc.c b/drivers/phy/rockchip/phy-rockchip-emmc.c
index b0d1093..b237360 100644
--- a/drivers/phy/rockchip/phy-rockchip-emmc.c
+++ b/drivers/phy/rockchip/phy-rockchip-emmc.c
@@ -79,6 +79,9 @@
#define PHYCTRL_IS_CALDONE(x) \
((((x) >> PHYCTRL_CALDONE_SHIFT) & \
PHYCTRL_CALDONE_MASK) == PHYCTRL_CALDONE_DONE)
+#define PHYCTRL_IS_DLLRDY(x) \
+ ((((x) >> PHYCTRL_DLLRDY_SHIFT) & \
+ PHYCTRL_DLLRDY_MASK) == PHYCTRL_DLLRDY_DONE)

struct rockchip_emmc_phy {
unsigned int reg_offset;
@@ -93,7 +96,6 @@ static int rockchip_emmc_phy_power(struct phy *phy, bool on_off)
unsigned int dllrdy;
unsigned int freqsel = PHYCTRL_FREQSEL_200M;
unsigned long rate;
- unsigned long timeout;
int ret;

/*
@@ -217,28 +219,15 @@ static int rockchip_emmc_phy_power(struct phy *phy, bool on_off)
* NOTE: There appear to be corner cases where the DLL seems to take
* extra long to lock for reasons that aren't understood. In some
* extreme cases we've seen it take up to over 10ms (!). We'll be
- * generous and give it 50ms. We still busy wait here because:
- * - In most cases it should be super fast.
- * - This is not called lots during normal operation so it shouldn't
- * be a power or performance problem to busy wait. We expect it
- * only at boot / resume. In both cases, eMMC is probably on the
- * critical path so busy waiting a little extra time should be OK.
+ * generous and give it 50ms.
*/
- timeout = jiffies + msecs_to_jiffies(50);
- do {
- udelay(1);
-
- regmap_read(rk_phy->reg_base,
- rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
- &dllrdy);
- dllrdy = (dllrdy >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK;
- if (dllrdy == PHYCTRL_DLLRDY_DONE)
- break;
- } while (!time_after(jiffies, timeout));
-
- if (dllrdy != PHYCTRL_DLLRDY_DONE) {
- pr_err("rockchip_emmc_phy_power: dllrdy timeout.\n");
- return -ETIMEDOUT;
+ ret = regmap_read_poll_timeout(rk_phy->reg_base,
+ rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
+ dllrdy, PHYCTRL_IS_DLLRDY(dllrdy),
+ 0, 50 * USEC_PER_MSEC);
+ if (ret) {
+ pr_err("%s: dllrdy failed. ret=%d\n", __func__, ret);
+ return ret;
}

return 0;
--
2.7.4
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