From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755710AbcEaHsj (ORCPT ); Tue, 31 May 2016 03:48:39 -0400 Received: from mail-io0-f195.google.com ([209.85.223.195]:36324 "EHLO mail-io0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755313AbcEaHsd (ORCPT ); Tue, 31 May 2016 03:48:33 -0400 MIME-Version: 1.0 In-Reply-To: <1464626385-19253-5-git-send-email-peter.senna@collabora.com> References: <1464626385-19253-1-git-send-email-peter.senna@collabora.com> <1464626385-19253-5-git-send-email-peter.senna@collabora.com> Date: Tue, 31 May 2016 09:48:32 +0200 Message-ID: Subject: Re: [PATCH 4/5] drm/bridge: Add driver for GE B850v3 LVDS/DP++ Bridge From: Enric Balletbo Serra To: Peter Senna Tschudin Cc: airlied@linux.ie, akpm@linux-foundation.org, David Miller , "devicetree@vger.kernel.org" , dri-devel , Enric Balletbo i Serra , Kumar Gala , Greg Kroah-Hartman , =?UTF-8?Q?Heiko_St=C3=BCbner?= , Ian Campbell , jslaby@suse.cz, kernel@pengutronix.de, "linux-arm-kernel@lists.infradead.org" , linux@armlinux.org.uk, linux-kernel@vger.kernel.org, linux@roeck-us.net, Mark Rutland , martin.donnelly@ge.com, martyn.welch@collabora.co.uk, Mauro Carvalho Chehab , Pawel Moll , Philipp Zabel , rmk+kernel@armlinux.org.uk, Rob Herring , shawnguo@kernel.org, Takashi Iwai , Thierry Reding , ykk@rock-chips.com Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Peter, Just some comments that I received when I submitted my bridge patches and that I think can help you ... 2016-05-30 18:39 GMT+02:00 Peter Senna Tschudin : > This driver creates a drm_bridge and a drm_connector for the LVDS to DP++ > display bridge of the GE B850v3(imx6q-b850v3.dts). There are two physical > bridges on the video signal pipeline: a STDP4028(LVDS to DP) and a > STDP2690(DP to DP++). However the physical bridges are automatically > configured by the input video signal, and the driver has no access to > the video processing pipeline. The driver is only needed to read EDID > from the STDP2690 and to handle HPD events from the STDP4028. The driver > communicates with both bridges over i2c. The video signal pipeline is as > follows: > > Host -> LVDS|--(STDP4028)--|DP -> DP|--(STDP2690)--|DP++ -> Video output > > Signed-off-by: Peter Senna Tschudin > --- > MAINTAINERS | 8 + > drivers/gpu/drm/bridge/Kconfig | 8 + > drivers/gpu/drm/bridge/Makefile | 1 + > drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c | 397 +++++++++++++++++++++++++++++ > 4 files changed, 414 insertions(+) > create mode 100644 drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 3273ffa..7bb5e89 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -5009,6 +5009,14 @@ W: https://linuxtv.org > S: Maintained > F: drivers/media/radio/radio-gemtek* > > +GENERAL ELECTRIC B850V3 LVDS/DP++ BRIDGE > +M: Martin Donnelly > +M: Peter Senna Tschudin > +M: Martyn Welch > +S: Maintained > +F: drivers/gpu/drm/bridge/ge_b850v3_dp2.c > +F: Documentation/devicetree/bindings/ge/b850v3_dp2_bridge.txt > + > GENERIC GPIO I2C DRIVER > M: Haavard Skinnemoen > S: Supported > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig > index 8f7423f..e9c32fc 100644 > --- a/drivers/gpu/drm/bridge/Kconfig > +++ b/drivers/gpu/drm/bridge/Kconfig > @@ -52,4 +52,12 @@ config DRM_PARADE_PS8622 > > source "drivers/gpu/drm/bridge/analogix/Kconfig" > > +config DRM_GE_B850V3_LVDS_DP > + tristate "LVDS/DP bridge" > + depends on OF > + select DRM_KMS_HELPER > + select DRM_PANEL > + ---help--- > + Driver for GE B850v3 DP2 LVDS to DP+ Bridge > + I think the maintainer prefers the entries ordered alphabetically (by vendor, then name), so your config should go before "config DRM_NXP_PTN3460" > endmenu > diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile > index 96b13b3..ba2e355 100644 > --- a/drivers/gpu/drm/bridge/Makefile > +++ b/drivers/gpu/drm/bridge/Makefile > @@ -6,3 +6,4 @@ obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o > obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o > obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o > obj-$(CONFIG_DRM_ANALOGIX_DP) += analogix/ > +obj-$(CONFIG_DRM_GE_B850V3_LVDS_DP) += ge_b850v3_lvds_dp.o Same here, this needs to be sorted by vendor, then name as well. Also I think is preferred use hyphens like the others drivers. Hmm, I see now that CONFIG_DRM_ANALOGIX_DP is not sorted, but I guess the preferred is be sorted. > diff --git a/drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c b/drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c > new file mode 100644 > index 0000000..37a4e7a > --- /dev/null > +++ b/drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c > @@ -0,0 +1,397 @@ > +/* > + * Driver for GE B850v3 DP display bridge > + > + * Copyright (c) 2016, Collabora Ltd. > + * Copyright (c) 2016, General Electric Company > + > + * This program is free software; you can redistribute it and/or modify it > + * under the terms and conditions of the GNU General Public License, > + * version 2, as published by the Free Software Foundation. > + > + * This program is distributed in the hope it will be useful, but WITHOUT > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for > + * more details. > + > + * You should have received a copy of the GNU General Public License > + * along with this program. If not, see . > + > + * This driver creates a drm_bridge and a drm_connector for the LVDS to DP++ > + * display bridge of the GE B850v3. There are two physical bridges on the video > + * signal pipeline: a STDP4028(LVDS to DP) and a STDP2690(DP to DP++). However > + * the physical bridges are automatically configured by the input video signal, > + * and the driver has no access to the video processing pipeline. The driver is > + * only needed to read EDID from the STDP2690 and to handle HPD events from the > + * STDP4028. The driver communicates with both bridges over i2c. The video > + * signal pipeline is as follows: > + * > + * Host -> LVDS|--(STDP4028)--|DP -> DP|--(STDP2690)--|DP++ -> Video output > + > + * > + */ > +#include > +#include > +#include > +#include > +#include "drm_crtc.h" > +#include "drm_crtc_helper.h" > +#include "drm_edid.h" > +#include "drmP.h" > + > +#define EDID_EXT_BLOCK_CNT 0x7E > + > +#define STDP4028_IRQ_OUT_CONF_REG 0x02 > +#define STDP4028_DPTX_IRQ_EN_REG 0x3C > +#define STDP4028_DPTX_IRQ_STS_REG 0x3D > +#define STDP4028_DPTX_STS_REG 0x3E > + > +#define STDP4028_DPTX_DP_IRQ_EN 0x1000 > + > +#define STDP4028_DPTX_HOTPLUG_IRQ_EN 0x0400 > +#define STDP4028_DPTX_LINK_CH_IRQ_EN 0x2000 > +#define STDP4028_DPTX_IRQ_CONFIG \ > + (STDP4028_DPTX_LINK_CH_IRQ_EN | STDP4028_DPTX_HOTPLUG_IRQ_EN) > + > +#define STDP4028_DPTX_HOTPLUG_STS 0x0200 > +#define STDP4028_DPTX_LINK_STS 0x1000 > +#define STDP4028_CON_STATE_CONNECTED \ > + (STDP4028_DPTX_HOTPLUG_STS | STDP4028_DPTX_LINK_STS) > + > +#define STDP4028_DPTX_HOTPLUG_CH_STS 0x0400 > +#define STDP4028_DPTX_LINK_CH_STS 0x2000 > +#define STDP4028_DPTX_IRQ_CLEAR \ > + (STDP4028_DPTX_LINK_CH_STS | STDP4028_DPTX_HOTPLUG_CH_STS) > + > +struct ge_b850v3_lvds_dp { > + struct drm_connector connector; > + struct drm_bridge bridge; > + struct i2c_client *ge_b850v3_lvds_dp_i2c; > + struct i2c_client *edid_i2c; > + struct edid *edid; > +}; > + > +static inline struct ge_b850v3_lvds_dp * > + bridge_to_ge_b850v3_lvds_dp(struct drm_bridge *bridge) > +{ > + return container_of(bridge, struct ge_b850v3_lvds_dp, bridge); > +} > + > +static inline struct ge_b850v3_lvds_dp * > + connector_to_ge_b850v3_lvds_dp(struct drm_connector *connector) > +{ > + return container_of(connector, struct ge_b850v3_lvds_dp, connector); > +} > + > +static void ge_b850v3_lvds_dp_pre_enable(struct drm_bridge *bridge) > +{ > +} > + You don't need to keep empty callbacks for the (pre/post) enable/disable drm_bridge ops anymore so you can remove this function and the below. > +static void ge_b850v3_lvds_dp_enable(struct drm_bridge *bridge) > +{ > +} > + > +static void ge_b850v3_lvds_dp_disable(struct drm_bridge *bridge) > +{ > +} > + > +static void ge_b850v3_lvds_dp_post_disable(struct drm_bridge *bridge) > +{ > +} > + > +u8 *stdp2690_get_edid(struct i2c_client *client) > +{ > + struct i2c_adapter *adapter = client->adapter; > + unsigned char start = 0x00; > + unsigned int total_size; > + u8 *block = kmalloc(EDID_LENGTH, GFP_KERNEL); > + > + struct i2c_msg msgs[] = { > + { > + .addr = client->addr, > + .flags = 0, > + .len = 1, > + .buf = &start, > + }, { > + .addr = client->addr, > + .flags = I2C_M_RD, > + .len = EDID_LENGTH, > + .buf = block, > + } > + }; > + > + if (!block) > + return NULL; > + > + if (i2c_transfer(adapter, msgs, 2) != 2) { > + DRM_ERROR("Unable to read EDID.\n"); > + goto err; > + } > + > + if (!drm_edid_block_valid(block, 0, false, NULL)) { > + DRM_ERROR("Invalid EDID block\n"); > + goto err; > + } > + > + total_size = (block[EDID_EXT_BLOCK_CNT] + 1) * EDID_LENGTH; > + if (total_size > EDID_LENGTH) { > + kfree(block); > + block = kmalloc(total_size, GFP_KERNEL); > + if (!block) > + return NULL; > + > + /* Yes, read the entire buffer, and do not skip the first > + * EDID_LENGTH bytes. > + */ > + start = 0x00; > + msgs[1].len = total_size; > + msgs[1].buf = block; > + > + if (i2c_transfer(adapter, msgs, 2) != 2) { > + DRM_ERROR("Unable to read EDID extension blocks.\n"); > + goto err; > + } > + } > + > + return block; > + > +err: > + kfree(block); > + return NULL; > +} > + > +static int ge_b850v3_lvds_dp_get_modes(struct drm_connector *connector) > +{ > + struct ge_b850v3_lvds_dp *ptn_bridge; > + struct i2c_client *client; > + u8 *block; > + int num_modes; > + > + ptn_bridge = connector_to_ge_b850v3_lvds_dp(connector); Move this assignation to ptn_bridge declaration > + client = ptn_bridge->edid_i2c; > + > + block = stdp2690_get_edid(client); I think you can remove the client variable and pass ptn_bridge->edid_i2c directly to the stdp2690_get_edid function. Note that get_modes is called several times and can be called from userspace, you are allocating memory on every call to get_modes that I think is not released or I'm missing something? > + ptn_bridge->edid = (struct edid *) block; > + What if block is NULL here ? > + drm_mode_connector_update_edid_property(connector, ptn_bridge->edid); > + num_modes = drm_add_edid_modes(connector, ptn_bridge->edid); > + > + return num_modes; nit: return drm_add_edid_modes(connector, ptn_bridge->edid); ? And remove num_modes ? > +} > + > +static struct drm_encoder > +*ge_b850v3_lvds_dp_best_encoder(struct drm_connector *connector) > +{ > + struct ge_b850v3_lvds_dp *ptn_bridge = > + connector_to_ge_b850v3_lvds_dp(connector); > + > + return ptn_bridge->bridge.encoder; > +} > + > +static const struct > +drm_connector_helper_funcs ge_b850v3_lvds_dp_connector_helper_funcs = { > + .get_modes = ge_b850v3_lvds_dp_get_modes, > + .best_encoder = ge_b850v3_lvds_dp_best_encoder, > +}; > + > +static enum drm_connector_status ge_b850v3_lvds_dp_detect( > + struct drm_connector *connector, bool force) > +{ > + struct ge_b850v3_lvds_dp *ptn_bridge = > + connector_to_ge_b850v3_lvds_dp(connector); > + struct i2c_client *ge_b850v3_lvds_dp_i2c = > + ptn_bridge->ge_b850v3_lvds_dp_i2c; > + s32 link_state; > + > + link_state = i2c_smbus_read_word_data(ge_b850v3_lvds_dp_i2c, > + STDP4028_DPTX_STS_REG); > + > + if (link_state == STDP4028_CON_STATE_CONNECTED) > + return connector_status_connected; > + > + if (link_state == 0) > + return connector_status_disconnected; > + > + return connector_status_unknown; > +} > + > +static void ge_b850v3_lvds_dp_connector_force(struct drm_connector *connector) > +{ > +} > + Guess you can remove this empty callback. > +static void ge_b850v3_lvds_dp_connector_destroy(struct drm_connector *connector) > +{ > + drm_connector_cleanup(connector); > +} > + > +static const struct drm_connector_funcs ge_b850v3_lvds_dp_connector_funcs = { > + .dpms = drm_helper_connector_dpms, > + .fill_modes = drm_helper_probe_single_connector_modes, > + .detect = ge_b850v3_lvds_dp_detect, > + .destroy = ge_b850v3_lvds_dp_connector_destroy, > + .force = ge_b850v3_lvds_dp_connector_force, Remove .force > +}; > + > +static irqreturn_t ge_b850v3_lvds_dp_irq_handler(int irq, void *dev_id) > +{ > + struct ge_b850v3_lvds_dp *ptn_bridge = dev_id; > + struct i2c_client *ge_b850v3_lvds_dp_i2c > + = ptn_bridge->ge_b850v3_lvds_dp_i2c; > + > + i2c_smbus_write_word_data(ge_b850v3_lvds_dp_i2c, > + STDP4028_DPTX_IRQ_STS_REG, STDP4028_DPTX_IRQ_CLEAR); > + > + if (ptn_bridge->connector.dev) > + drm_kms_helper_hotplug_event(ptn_bridge->connector.dev); > + > + return IRQ_HANDLED; > + Remove the empty line. > +} > + > +static int ge_b850v3_lvds_dp_attach(struct drm_bridge *bridge) > +{ > + struct ge_b850v3_lvds_dp *ptn_bridge > + = bridge_to_ge_b850v3_lvds_dp(bridge); > + struct drm_connector *connector = &ptn_bridge->connector; > + struct i2c_client *ge_b850v3_lvds_dp_i2c > + = ptn_bridge->ge_b850v3_lvds_dp_i2c; > + int ret; > + > + if (!bridge->encoder) { > + DRM_ERROR("Parent encoder object not found"); > + return -ENODEV; > + } > + > + connector->polled = DRM_CONNECTOR_POLL_HPD; > + > + drm_connector_helper_add(connector, > + &ge_b850v3_lvds_dp_connector_helper_funcs); > + > + ret = drm_connector_init(bridge->dev, connector, > + &ge_b850v3_lvds_dp_connector_funcs, > + DRM_MODE_CONNECTOR_DisplayPort); > + if (ret) { > + DRM_ERROR("Failed to initialize connector with drm\n"); > + return ret; > + } > + > + ret = drm_mode_connector_attach_encoder(connector, bridge->encoder); > + if (ret) > + return ret; > + > + drm_bridge_enable(bridge); > + if (ge_b850v3_lvds_dp_i2c->irq) { > + drm_helper_hpd_irq_event(connector->dev); > + > + ret = devm_request_threaded_irq(&ge_b850v3_lvds_dp_i2c->dev, > + ge_b850v3_lvds_dp_i2c->irq, NULL, > + ge_b850v3_lvds_dp_irq_handler, > + IRQF_TRIGGER_HIGH | IRQF_ONESHOT, > + "ge_b850v3_lvds_dp", ptn_bridge); > + if (ret) > + return ret; > + } > + > + return 0; > +} > + > +static const struct drm_bridge_funcs ge_b850v3_lvds_dp_funcs = { > + .pre_enable = ge_b850v3_lvds_dp_pre_enable, > + .enable = ge_b850v3_lvds_dp_enable, > + .disable = ge_b850v3_lvds_dp_disable, > + .post_disable = ge_b850v3_lvds_dp_post_disable, Remove the above empty callbacks. > + .attach = ge_b850v3_lvds_dp_attach, > +}; > + > +static int ge_b850v3_lvds_dp_probe(struct i2c_client *ge_b850v3_lvds_dp_i2c, > + const struct i2c_device_id *id) > +{ > + struct device *dev = &ge_b850v3_lvds_dp_i2c->dev; > + struct ge_b850v3_lvds_dp *ptn_bridge; > + Remove this empty line between these two blocks. > + int ret; > + u32 edid_i2c_reg; > + > + ptn_bridge = devm_kzalloc(dev, sizeof(*ptn_bridge), GFP_KERNEL); > + if (!ptn_bridge) > + return -ENOMEM; > + > + ptn_bridge->ge_b850v3_lvds_dp_i2c = ge_b850v3_lvds_dp_i2c; > + ptn_bridge->bridge.driver_private = ptn_bridge; > + i2c_set_clientdata(ge_b850v3_lvds_dp_i2c, ptn_bridge); > + > + ret = of_property_read_u32(dev->of_node, "edid-reg", &edid_i2c_reg); > + if (ret) { > + dev_err(dev, "edid-reg not specified, aborting...\n"); Use DRM_ERROR? > + return -ENODEV; > + } > + > + ptn_bridge->edid_i2c = devm_kzalloc(dev, > + sizeof(struct i2c_client), GFP_KERNEL); > + > + if (!ptn_bridge->edid_i2c) > + return -ENOMEM; > + > + memcpy(ptn_bridge->edid_i2c, ge_b850v3_lvds_dp_i2c, > + sizeof(struct i2c_client)); > + > + ptn_bridge->edid_i2c->addr = (unsigned short) edid_i2c_reg; > + Remove empty line. > + > + /* Configures the bridge to re-enable interrupts after each ack */ > + i2c_smbus_write_word_data(ge_b850v3_lvds_dp_i2c, > + STDP4028_IRQ_OUT_CONF_REG, STDP4028_DPTX_DP_IRQ_EN); > + i2c_smbus_write_word_data(ge_b850v3_lvds_dp_i2c, > + STDP4028_DPTX_IRQ_EN_REG, STDP4028_DPTX_IRQ_CONFIG); > + > + /* Clear pending interrupts since power up. */ > + i2c_smbus_write_word_data(ge_b850v3_lvds_dp_i2c, > + STDP4028_DPTX_IRQ_STS_REG, STDP4028_DPTX_IRQ_CLEAR); > + > + ptn_bridge->bridge.funcs = &ge_b850v3_lvds_dp_funcs; > + ptn_bridge->bridge.of_node = dev->of_node; > + ret = drm_bridge_add(&ptn_bridge->bridge); > + if (ret) { > + DRM_ERROR("Failed to add bridge\n"); > + return ret; > + } > + > + return 0; > +} > + > +static int ge_b850v3_lvds_dp_remove(struct i2c_client *ge_b850v3_lvds_dp_i2c) > +{ > + struct ge_b850v3_lvds_dp *ptn_bridge = > + i2c_get_clientdata(ge_b850v3_lvds_dp_i2c); > + > + drm_bridge_remove(&ptn_bridge->bridge); > + > + return 0; > +} > + > +static const struct i2c_device_id ge_b850v3_lvds_dp_i2c_table[] = { > + {"b850v3_lvds_dp", 0}, > + {}, > +}; > +MODULE_DEVICE_TABLE(i2c, ge_b850v3_lvds_dp_i2c_table); > + > +static const struct of_device_id ge_b850v3_lvds_dp_match[] = { > + { .compatible = "ge,b850v3_lvds_dp" }, > + {}, > +}; > +MODULE_DEVICE_TABLE(of, ge_b850v3_lvds_dp_match); > + > +static struct i2c_driver ge_b850v3_lvds_dp_driver = { > + .id_table = ge_b850v3_lvds_dp_i2c_table, > + .probe = ge_b850v3_lvds_dp_probe, > + .remove = ge_b850v3_lvds_dp_remove, > + .driver = { > + .name = "ge,b850v3_lvds_dp", > + .of_match_table = ge_b850v3_lvds_dp_match, > + }, > +}; > +module_i2c_driver(ge_b850v3_lvds_dp_driver); > + > +MODULE_AUTHOR("Peter Senna Tschudin "); > +MODULE_AUTHOR("Martyn Welch "); > +MODULE_DESCRIPTION("GE LVDS to DP++ bridge)"); > +MODULE_LICENSE("GPL v2"); > -- > 2.5.5 > Best regards, Enric