From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753123AbeBEMyV (ORCPT ); Mon, 5 Feb 2018 07:54:21 -0500 Received: from mx07-00178001.pphosted.com ([62.209.51.94]:42075 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753140AbeBEMyI (ORCPT ); Mon, 5 Feb 2018 07:54:08 -0500 From: Philippe CORNU To: Andrzej Hajda , Archit Taneja , Laurent Pinchart , David Airlie , "Brian Norris" , Benjamin Gaignard , Bhumika Goyal , "dri-devel@lists.freedesktop.org" , "linux-kernel@vger.kernel.org" , Sandy Huang , Heiko Stubner , "linux-arm-kernel@lists.infradead.org" , "linux-rockchip@lists.infradead.org" CC: Yannick FERTRE , Vincent ABRIOU , Alexandre TORGUE Subject: Re: [PATCH] drm/bridge/synopsys: dsi: Add read feature Thread-Topic: [PATCH] drm/bridge/synopsys: dsi: Add read feature Thread-Index: AQHTnmkdhd8RvGsBqE+ovznsYCM5oaOVsrqA Date: Mon, 5 Feb 2018 12:52:19 +0000 Message-ID: <1fce104e-7cab-86a1-db49-5306e04d10b7@st.com> References: <20180204213104.17834-1-philippe.cornu@st.com> <81cb1f26-96f0-bdc6-28bc-4a7bda5a9459@samsung.com> In-Reply-To: <81cb1f26-96f0-bdc6-28bc-4a7bda5a9459@samsung.com> Accept-Language: fr-FR, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: user-agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.6.0 x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.75.127.51] Content-Type: text/plain; charset="utf-8" Content-ID: MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:,, definitions=2018-02-05_02:,, signatures=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from base64 to 8bit by mail.home.local id w15CsWiv027836 Hi Andrzej, And many thanks Philippe :-) On 02/05/2018 11:07 AM, Andrzej Hajda wrote: > On 04.02.2018 22:31, Philippe Cornu wrote: >> This patch adds the DCS/GENERIC DSI read feature. >> >> Signed-off-by: Philippe Cornu > > Reviewed-by: Andrzej Hajda > > If there will be no objections I will merge it at the end of the week. > >  -- > Regards > Andrzej > >> --- >> Extra notes: >> DSI read tests have been performed with DCS & GENERIC, short & long >> commands, on two different panels. >> The maximum fifo size (32*32-bit = 128 bytes on stm32) has been >> verified too. >> >> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 58 +++++++++++++++++++++------ >> 1 file changed, 45 insertions(+), 13 deletions(-) >> >> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c >> index e9422d05e897..65aeb3f78b48 100644 >> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c >> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c >> @@ -397,18 +397,46 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi, >> return dw_mipi_dsi_gen_pkt_hdr_write(dsi, le32_to_cpu(word)); >> } >> >> +static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi, >> + const struct mipi_dsi_msg *msg) >> +{ >> + int i, j, ret, len = msg->rx_len; >> + u8 *buf = msg->rx_buf; >> + u32 val; >> + >> + /* Wait end of the read operation */ >> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS, >> + val, !(val & GEN_RD_CMD_BUSY), >> + 1000, CMD_PKT_STATUS_TIMEOUT_US); >> + if (ret) { >> + dev_err(dsi->dev, "Timeout during read operation\n"); >> + return ret; >> + } >> + >> + for (i = 0; i < len; i += 4) { >> + /* Read fifo must not be empty before all bytes are read */ >> + ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS, >> + val, !(val & GEN_PLD_R_EMPTY), >> + 1000, CMD_PKT_STATUS_TIMEOUT_US); >> + if (ret) { >> + dev_err(dsi->dev, "Read payload FIFO is empty\n"); >> + return ret; >> + } >> + >> + val = dsi_read(dsi, DSI_GEN_PLD_DATA); >> + for (j = 0; j < 4 && j + i < len; j++) >> + buf[i + j] = val >> (8 * j); >> + } >> + >> + return ret; >> +} >> + >> static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host, >> const struct mipi_dsi_msg *msg) >> { >> struct dw_mipi_dsi *dsi = host_to_dsi(host); >> struct mipi_dsi_packet packet; >> - int ret; >> - >> - if (msg->rx_buf || msg->rx_len) { >> - /* TODO dw drv improvements: implement read feature */ >> - dev_warn(dsi->dev, "read operations not yet implemented\n"); >> - return -EINVAL; >> - } >> + int ret, nb_bytes; >> >> ret = mipi_dsi_create_packet(&packet, msg); >> if (ret) { >> @@ -422,12 +450,16 @@ static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host, >> if (ret) >> return ret; >> >> - /* >> - * TODO Only transmitted size is returned as actual driver does >> - * not support dcs/generic reads. Please update return value when >> - * delivering the read feature. >> - */ >> - return packet.size; >> + if (msg->rx_buf && msg->rx_len) { >> + ret = dw_mipi_dsi_read(dsi, msg); >> + if (ret) >> + return ret; >> + nb_bytes = msg->rx_len; >> + } else { >> + nb_bytes = packet.size; >> + } >> + >> + return nb_bytes; >> } >> >> static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = { > >