drm/bridge: tc358767: Simplify tc_poll_timeout()

Implementation of tc_poll_timeout() is almost a 100% copy-and-paste of
the code for regmap_read_poll_timeout(). Replace copied code with a
call to the original. While at it change tc_poll_timeout to accept
"struct tc_data *" instead of "struct regmap *" for brevity. No
functional change intended.
Signed-off-by: Andrey Smirnov <andrew.smirnov@gmail.com>
Reviewed-by: Andrzej Hajda <a.hajda@samsung.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Andrzej Hajda <a.hajda@samsung.com>
Cc: Laurent Pinchart <Laurent.pinchart@ideasonboard.com>
Cc: Tomi Valkeinen <tomi.valkeinen@ti.com>
Cc: Andrey Gusakov <andrey.gusakov@cogentembedded.com>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Cc: Cory Tusar <cory.tusar@zii.aero>
Cc: Chris Healy <cphealy@gmail.com>
Cc: Lucas Stach <l.stach@pengutronix.de>
Cc: dri-devel@lists.freedesktop.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Andrzej Hajda <a.hajda@samsung.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190619052716.16831-2-andrew.smirnov@gmail.com

drivers/gpu/drm/bridge/tc358767.c

@@ -255,34 +255,21 @@ static inline struct tc_data *connector_to_tc(struct drm_connector *c)
 			goto err;				\
 	} while (0)
 
-static inline int tc_poll_timeout(struct regmap *map, unsigned int addr,
+static inline int tc_poll_timeout(struct tc_data *tc, unsigned int addr,
 				  unsigned int cond_mask,
 				  unsigned int cond_value,
 				  unsigned long sleep_us, u64 timeout_us)
 {
-	ktime_t timeout = ktime_add_us(ktime_get(), timeout_us);
 	unsigned int val;
-	int ret;
 
-	for (;;) {
-		ret = regmap_read(map, addr, &val);
-		if (ret)
-			break;
-		if ((val & cond_mask) == cond_value)
-			break;
-		if (timeout_us && ktime_compare(ktime_get(), timeout) > 0) {
-			ret = regmap_read(map, addr, &val);
-			break;
-		}
-		if (sleep_us)
-			usleep_range((sleep_us >> 2) + 1, sleep_us);
-	}
-	return ret ?: (((val & cond_mask) == cond_value) ? 0 : -ETIMEDOUT);
+	return regmap_read_poll_timeout(tc->regmap, addr, val,
+					(val & cond_mask) == cond_value,
+					sleep_us, timeout_us);
 }
 
 static int tc_aux_wait_busy(struct tc_data *tc, unsigned int timeout_ms)
 {
-	return tc_poll_timeout(tc->regmap, DP0_AUXSTATUS, AUX_BUSY, 0,
+	return tc_poll_timeout(tc, DP0_AUXSTATUS, AUX_BUSY, 0,
 			       1000, 1000 * timeout_ms);
 }
 
@@ -589,8 +576,7 @@ static int tc_aux_link_setup(struct tc_data *tc)
 	tc_write(DP1_PLLCTRL, PLLUPDATE | PLLEN);
 	tc_wait_pll_lock(tc);
 
-	ret = tc_poll_timeout(tc->regmap, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 1,
-			      1000);
+	ret = tc_poll_timeout(tc, DP_PHY_CTRL, PHY_RDY, PHY_RDY, 1, 1000);
 	if (ret == -ETIMEDOUT) {
 		dev_err(tc->dev, "Timeout waiting for PHY to become ready");
 		return ret;