From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Subject: [PATCH 03/15] drm/dsi: Add mipi_dsi_set_maximum_return_packet_size() helper Date: Mon, 13 Oct 2014 12:16:23 +0200 Message-ID: <1413195395-3355-3-git-send-email-thierry.reding@gmail.com> References: <1413195395-3355-1-git-send-email-thierry.reding@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wg0-f46.google.com (mail-wg0-f46.google.com [74.125.82.46]) by gabe.freedesktop.org (Postfix) with ESMTP id B7F9B89CD9 for ; Mon, 13 Oct 2014 03:16:42 -0700 (PDT) Received: by mail-wg0-f46.google.com with SMTP id l18so8310033wgh.29 for ; Mon, 13 Oct 2014 03:16:41 -0700 (PDT) In-Reply-To: <1413195395-3355-1-git-send-email-thierry.reding@gmail.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" To: dri-devel@lists.freedesktop.org Cc: Andrzej Hajda List-Id: dri-devel@lists.freedesktop.org From: YoungJun Cho This function can be used to set the maximum return packet size for a MIPI DSI peripheral. Signed-off-by: YoungJun Cho [treding: endianess, kerneldoc, return value] Signed-off-by: Thierry Reding --- drivers/gpu/drm/drm_mipi_dsi.c | 30 ++++++++++++++++++++++++++++++ include/drm/drm_mipi_dsi.h | 2 ++ 2 files changed, 32 insertions(+) diff --git a/drivers/gpu/drm/drm_mipi_dsi.c b/drivers/gpu/drm/drm_mipi_dsi.c index 1702ffd07986..27fc6dac5e4a 100644 --- a/drivers/gpu/drm/drm_mipi_dsi.c +++ b/drivers/gpu/drm/drm_mipi_dsi.c @@ -198,6 +198,36 @@ int mipi_dsi_detach(struct mipi_dsi_device *dsi) } EXPORT_SYMBOL(mipi_dsi_detach); +/* + * mipi_dsi_set_maximum_return_packet_size() - specify the maximum size of the + * the payload in a long packet transmitted from the peripheral back to the + * host processor + * @dsi: DSI peripheral device + * @value: the maximum size of the payload + * + * Return: 0 on success or a negative error code on failure. + */ +int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi, + u16 value) +{ + u8 tx[2] = { value & 0xff, value >> 8 }; + struct mipi_dsi_msg msg; + ssize_t err; + + memset(&msg, 0, sizeof(msg)); + msg.channel = dsi->channel; + msg.type = MIPI_DSI_SET_MAXIMUM_RETURN_PACKET_SIZE; + msg.tx_len = sizeof(tx); + msg.tx_buf = tx; + + err = dsi->host->ops->transfer(dsi->host, &msg); + if (err < 0) + return err; + + return 0; +} +EXPORT_SYMBOL(mipi_dsi_set_maximum_return_packet_size); + /** * mipi_dsi_dcs_write_buffer() - transmit a DCS command with payload * @dsi: DSI peripheral device diff --git a/include/drm/drm_mipi_dsi.h b/include/drm/drm_mipi_dsi.h index 836cc2b677d0..ef50b5d0de57 100644 --- a/include/drm/drm_mipi_dsi.h +++ b/include/drm/drm_mipi_dsi.h @@ -132,6 +132,8 @@ static inline struct mipi_dsi_device *to_mipi_dsi_device(struct device *dev) int mipi_dsi_attach(struct mipi_dsi_device *dsi); int mipi_dsi_detach(struct mipi_dsi_device *dsi); +int mipi_dsi_set_maximum_return_packet_size(struct mipi_dsi_device *dsi, + u16 value); ssize_t mipi_dsi_dcs_write_buffer(struct mipi_dsi_device *dsi, const void *data, size_t len); ssize_t mipi_dsi_dcs_write(struct mipi_dsi_device *dsi, u8 cmd, -- 2.1.2