From 12dfe7c4d9c53442efcb4113cff505f60d654906 Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Tue, 18 Jun 2019 22:27:10 -0700 Subject: [PATCH] drm/bridge: tc358767: Use reported AUX transfer size Don't assume that requested data transfer size is the same as amount of data that was transferred. Change the code to get that information from DP0_AUXSTATUS instead. Since the check for AUX_BUSY in tc_aux_get_status() is pointless (it will always called after tc_aux_wait_busy()) and there's only one user of it, inline its code into tc_aux_transfer() instead of trying to accommodate the change above. Signed-off-by: Andrey Smirnov Reviewed-by: Andrzej Hajda Reviewed-by: Tomi Valkeinen Cc: Andrzej Hajda Cc: Laurent Pinchart Cc: Tomi Valkeinen Cc: Andrey Gusakov Cc: Philipp Zabel Cc: Cory Tusar Cc: Chris Healy Cc: Lucas Stach Cc: dri-devel@lists.freedesktop.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Andrzej Hajda Link: https://patchwork.freedesktop.org/patch/msgid/20190619052716.16831-10-andrew.smirnov@gmail.com --- drivers/gpu/drm/bridge/tc358767.c | 40 ++++++++++--------------------- 1 file changed, 12 insertions(+), 28 deletions(-) diff --git a/drivers/gpu/drm/bridge/tc358767.c b/drivers/gpu/drm/bridge/tc358767.c index 0457ca4508c4..b60cd3607f4f 100644 --- a/drivers/gpu/drm/bridge/tc358767.c +++ b/drivers/gpu/drm/bridge/tc358767.c @@ -143,10 +143,10 @@ #define DP0_AUXWDATA(i) (0x066c + (i) * 4) #define DP0_AUXRDATA(i) (0x067c + (i) * 4) #define DP0_AUXSTATUS 0x068c -#define AUX_STATUS_MASK 0xf0 -#define AUX_STATUS_SHIFT 4 -#define AUX_TIMEOUT BIT(1) -#define AUX_BUSY BIT(0) +#define AUX_BYTES GENMASK(15, 8) +#define AUX_STATUS GENMASK(7, 4) +#define AUX_TIMEOUT BIT(1) +#define AUX_BUSY BIT(0) #define DP0_AUXI2CADR 0x0698 /* Link Training */ @@ -289,29 +289,6 @@ static int tc_aux_wait_busy(struct tc_data *tc, unsigned int timeout_ms) 1000, 1000 * timeout_ms); } -static int tc_aux_get_status(struct tc_data *tc, u8 *reply) -{ - int ret; - u32 value; - - ret = regmap_read(tc->regmap, DP0_AUXSTATUS, &value); - if (ret < 0) - return ret; - - if (value & AUX_BUSY) { - dev_err(tc->dev, "aux busy!\n"); - return -EBUSY; - } - - if (value & AUX_TIMEOUT) { - dev_err(tc->dev, "aux access timeout!\n"); - return -ETIMEDOUT; - } - - *reply = (value & AUX_STATUS_MASK) >> AUX_STATUS_SHIFT; - return 0; -} - static int tc_aux_write_data(struct tc_data *tc, const void *data, size_t size) { @@ -347,6 +324,7 @@ static ssize_t tc_aux_transfer(struct drm_dp_aux *aux, struct tc_data *tc = aux_to_tc(aux); size_t size = min_t(size_t, DP_AUX_MAX_PAYLOAD_BYTES - 1, msg->size); u8 request = msg->request & ~DP_AUX_I2C_MOT; + u32 auxstatus; int ret; if (size == 0) @@ -384,10 +362,16 @@ static ssize_t tc_aux_transfer(struct drm_dp_aux *aux, if (ret) return ret; - ret = tc_aux_get_status(tc, &msg->reply); + ret = regmap_read(tc->regmap, DP0_AUXSTATUS, &auxstatus); if (ret) return ret; + if (auxstatus & AUX_TIMEOUT) + return -ETIMEDOUT; + + size = FIELD_GET(AUX_BYTES, auxstatus); + msg->reply = FIELD_GET(AUX_STATUS, auxstatus); + switch (request) { case DP_AUX_NATIVE_READ: case DP_AUX_I2C_READ: -- 2.45.2