linux-kernel - [PATCH v6 2/3] drm/bridge: ti-sn65dsi86: Use regmap_bulk

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Date:   Wed, 29 Sep 2021 22:05:56 -0500
From:   Bjorn Andersson <bjorn.andersson@...aro.org>
To:     Andrzej Hajda <a.hajda@...sung.com>,
        Neil Armstrong <narmstrong@...libre.com>,
        Robert Foss <robert.foss@...aro.org>,
        Laurent Pinchart <Laurent.pinchart@...asonboard.com>,
        Jonas Karlman <jonas@...boo.se>,
        Jernej Skrabec <jernej.skrabec@...il.com>,
        David Airlie <airlied@...ux.ie>,
        Daniel Vetter <daniel@...ll.ch>,
        Thierry Reding <thierry.reding@...il.com>,
        Uwe Kleine-König 
        <u.kleine-koenig@...gutronix.de>, Lee Jones <lee.jones@...aro.org>
Cc:     dri-devel@...ts.freedesktop.org, linux-kernel@...r.kernel.org,
        linux-pwm@...r.kernel.org, linux-arm-msm@...r.kernel.org,
        Doug Anderson <dianders@...gle.com>
Subject: [PATCH v6 2/3] drm/bridge: ti-sn65dsi86: Use regmap_bulk_write API

The multi-register u16 write operation can use regmap_bulk_write()
instead of two separate regmap_write() calls.

It's uncertain if this has any effect on the actual updates of the
underlying registers, but this at least gives the hardware the
opportunity and saves us one transation on the bus.

Signed-off-by: Bjorn Andersson <bjorn.andersson@...aro.org>
---

Changes since v5:
- Extracted this hunk from patch 3.

 drivers/gpu/drm/bridge/ti-sn65dsi86.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
index 41d48a393e7f..412fb6f564ea 100644
--- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
@@ -193,8 +193,9 @@ static const struct regmap_config ti_sn65dsi86_regmap_config = {
 static void ti_sn65dsi86_write_u16(struct ti_sn65dsi86 *pdata,
 				   unsigned int reg, u16 val)
 {
-	regmap_write(pdata->regmap, reg, val & 0xFF);
-	regmap_write(pdata->regmap, reg + 1, val >> 8);
+	u8 buf[2] = { val & 0xff, val >> 8 };
+
+	regmap_bulk_write(pdata->regmap, reg, buf, ARRAY_SIZE(buf));
 }
 
 static u32 ti_sn_bridge_get_dsi_freq(struct ti_sn65dsi86 *pdata)
-- 
2.32.0