Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754625AbdCBJmX (ORCPT ); Thu, 2 Mar 2017 04:42:23 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:59940 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754038AbdCBJle (ORCPT ); Thu, 2 Mar 2017 04:41:34 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 61B0A60A60 Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=architt@codeaurora.org Subject: Re: [PATCH V2 3/4] drm/bridge: Drivers for megachips-stdpxxxx-ge-b850v3-fw (LVDS-DP++) To: Peter Senna Tschudin References: <5278cd3e4c409ace0d62d6aedcc555b38b8a89a9.1488287639.git.peter.senna@collabora.com> <8f61b5c1-3c99-6657-2c0b-41a070b322af@codeaurora.org> <20170301103847.GC15134@collabora.com> Cc: airlied@linux.ie, akpm@linux-foundation.org, daniel.vetter@ffwll.ch, davem@davemloft.net, devicetree@vger.kernel.org, dri-devel@lists.freedesktop.org, enric.balletbo@collabora.com, eballetbo@gmail.com, galak@codeaurora.org, gregkh@linuxfoundation.org, heiko@sntech.de, ijc+devicetree@hellion.org.uk, javier@dowhile0.org, 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@arm.com, martin.donnelly@ge.com, martyn.welch@collabora.co.uk, mchehab@osg.samsung.com, pawel.moll@arm.com, peter.senna@gmail.com, p.zabel@pengutronix.de, thierry.reding@gmail.com, rmk+kernel@armlinux.org.uk, robh+dt@kernel.org, shawnguo@kernel.org, tiwai@suse.com, treding@nvidia.com, ykk@rock-chips.com, laurent.pinchart@ideasonboard.com, Rob Herring , Fabio Estevam From: Archit Taneja Message-ID: <5db055e1-ef17-757f-f247-313caea60cc1@codeaurora.org> Date: Thu, 2 Mar 2017 14:59:40 +0530 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:45.0) Gecko/20100101 Thunderbird/45.7.1 MIME-Version: 1.0 In-Reply-To: <20170301103847.GC15134@collabora.com> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 18881 Lines: 557 Hi Peter, On 3/1/2017 4:08 PM, Peter Senna Tschudin wrote: > Hi Archit, > > Thank you for the review! > > On Wed, Mar 01, 2017 at 09:38:48AM +0530, Archit Taneja wrote: >> >> >> On 02/28/2017 07:58 PM, Peter Senna Tschudin wrote: >>> The video processing pipeline on the second output on the GE B850v3: >>> >>> Host -> LVDS|--(STDP4028)--|DP -> DP|--(STDP2690)--|DP++ -> Video output >>> >>> Each bridge has a dedicated flash containing firmware for supporting the >>> custom design. The result is that in this design neither the STDP4028 >>> nor the STDP2690 behave as the stock bridges would. The compatible >>> strings include the suffix "-ge-b850v3-fw" to make it clear that the >>> driver is for the bridges with the firmware which is specific for the GE >>> B850v3. >>> >>> The driver is powerless to control the video processing pipeline, as the >>> two bridges behaves as a single one. The driver is only needed for >>> telling the host about EDID / HPD, and for giving the host powers to ack >>> interrupts. >>> >>> This driver adds one i2c_device for each bridge, but only one >>> drm_bridge. This design allows the creation of a functional connector >>> that is capable of reading EDID from the STDP2690 while handling >>> interrupts on the STDP4028. >>> >>> Cc: Laurent Pinchart >>> Cc: Martyn Welch >>> Cc: Martin Donnelly >>> Cc: Daniel Vetter >>> Cc: Enric Balletbo i Serra >>> Cc: Philipp Zabel >>> Cc: Rob Herring >>> Cc: Fabio Estevam >>> Cc: David Airlie >>> Cc: Thierry Reding >>> Cc: Thierry Reding >>> Cc: Archit Taneja >>> Cc: Enric Balletbo >>> Signed-off-by: Peter Senna Tschudin >>> --- >>> Changes from V1: >>> - Updated copyright year >>> - Fixed blank line issues >>> - Updated ge_b850v3_lvds_remove() to not rely on ge_b850v3_lvds_ptr->edid and >>> added a comment to explain the test. >>> - Fixed checkpatch strict warnings about continuation lines. In one case >>> fixing the warning would cause the continuation line to be over 80 chars and >>> that strict warning remains. >>> >>> drivers/gpu/drm/bridge/Kconfig | 11 + >>> drivers/gpu/drm/bridge/Makefile | 1 + >>> .../drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c | 411 +++++++++++++++++++++ >>> 3 files changed, 423 insertions(+) >>> create mode 100644 drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c >>> >>> diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig >>> index eb8688e..4a937f1 100644 >>> --- a/drivers/gpu/drm/bridge/Kconfig >>> +++ b/drivers/gpu/drm/bridge/Kconfig >>> @@ -48,6 +48,17 @@ config DRM_DW_HDMI_I2S_AUDIO >>> Support the I2S Audio interface which is part of the Synopsis >>> Designware HDMI block. >>> >>> +config DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW >>> + tristate "MegaChips stdp4028-ge-b850v3-fw and stdp2690-ge-b850v3-fw" >>> + depends on OF >>> + select DRM_KMS_HELPER >>> + select DRM_PANEL >>> + ---help--- >>> + This is a driver for the display bridges of >>> + GE B850v3 that convert dual channel LVDS >>> + to DP++. This is used with the i.MX6 imx-ldb >>> + driver. You are likely to say N here. >>> + >>> config DRM_NXP_PTN3460 >>> tristate "NXP PTN3460 DP/LVDS bridge" >>> depends on OF >>> diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile >>> index 2e83a785..af0b7cc 100644 >>> --- a/drivers/gpu/drm/bridge/Makefile >>> +++ b/drivers/gpu/drm/bridge/Makefile >>> @@ -5,6 +5,7 @@ obj-$(CONFIG_DRM_DUMB_VGA_DAC) += dumb-vga-dac.o >>> obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o >>> obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o >>> obj-$(CONFIG_DRM_DW_HDMI_I2S_AUDIO) += dw-hdmi-i2s-audio.o >>> +obj-$(CONFIG_DRM_MEGACHIPS_STDPXXXX_GE_B850V3_FW) += megachips-stdpxxxx-ge-b850v3-fw.o >>> obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o >>> obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o >>> obj-$(CONFIG_DRM_SIL_SII8620) += sil-sii8620.o >>> diff --git a/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c b/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c >>> new file mode 100644 >>> index 0000000..6f82a44 >>> --- /dev/null >>> +++ b/drivers/gpu/drm/bridge/megachips-stdpxxxx-ge-b850v3-fw.c >>> @@ -0,0 +1,411 @@ >>> +/* >>> + * Driver for MegaChips STDP4028 with GE B850v3 firmware (LVDS-DP) >>> + * Driver for MegaChips STDP2690 with GE B850v3 firmware (DP-DP++) >>> + >>> + * Copyright (c) 2017, Collabora Ltd. >>> + * Copyright (c) 2017, 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++). 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 >>> +#include >>> +#include >>> +#include >>> +#include >>> + >>> +#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) >>> + >>> +static DEFINE_MUTEX(ge_b850v3_lvds_dev_mutex); >>> + >>> +struct ge_b850v3_lvds { >>> + struct drm_connector connector; >>> + struct drm_bridge bridge; >>> + struct i2c_client *stdp4028_i2c; >>> + struct i2c_client *stdp2690_i2c; >>> + struct edid *edid; >>> +}; >>> + >>> +static struct ge_b850v3_lvds *ge_b850v3_lvds_ptr; >>> + >>> +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 data\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; >>> + } >>> + if (!drm_edid_block_valid(block, 1, false, NULL)) { >>> + DRM_ERROR("Invalid EDID data\n"); >>> + goto err; >>> + } >>> + } >>> + >>> + return block; >>> + >>> +err: >>> + kfree(block); >>> + return NULL; >>> +} >>> + >>> +static int ge_b850v3_lvds_get_modes(struct drm_connector *connector) >>> +{ >>> + struct i2c_client *client; >>> + int num_modes = 0; >>> + >>> + client = ge_b850v3_lvds_ptr->stdp2690_i2c; >>> + >>> + kfree(ge_b850v3_lvds_ptr->edid); >>> + ge_b850v3_lvds_ptr->edid = (struct edid *)stdp2690_get_edid(client); >>> + >>> + if (ge_b850v3_lvds_ptr->edid) { >>> + drm_mode_connector_update_edid_property(connector, >>> + ge_b850v3_lvds_ptr->edid); >>> + num_modes = drm_add_edid_modes(connector, >>> + ge_b850v3_lvds_ptr->edid); >>> + } >>> + >>> + return num_modes; >>> +} >>> + >>> +static enum drm_mode_status ge_b850v3_lvds_mode_valid( >>> + struct drm_connector *connector, struct drm_display_mode *mode) >>> +{ >>> + return MODE_OK; >>> +} >>> + >>> +static const struct >>> +drm_connector_helper_funcs ge_b850v3_lvds_connector_helper_funcs = { >>> + .get_modes = ge_b850v3_lvds_get_modes, >>> + .mode_valid = ge_b850v3_lvds_mode_valid, >>> +}; >>> + >>> +static enum drm_connector_status ge_b850v3_lvds_detect( >>> + struct drm_connector *connector, bool force) >>> +{ >>> + struct i2c_client *stdp4028_i2c = >>> + ge_b850v3_lvds_ptr->stdp4028_i2c; >>> + s32 link_state; >>> + >>> + link_state = i2c_smbus_read_word_data(stdp4028_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 const struct drm_connector_funcs ge_b850v3_lvds_connector_funcs = { >>> + .dpms = drm_atomic_helper_connector_dpms, >>> + .fill_modes = drm_helper_probe_single_connector_modes, >>> + .detect = ge_b850v3_lvds_detect, >>> + .destroy = drm_connector_cleanup, >>> + .reset = drm_atomic_helper_connector_reset, >>> + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state, >>> + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state, >>> +}; >>> + >>> +static irqreturn_t ge_b850v3_lvds_irq_handler(int irq, void *dev_id) >>> +{ >>> + struct i2c_client *stdp4028_i2c >>> + = ge_b850v3_lvds_ptr->stdp4028_i2c; >>> + >>> + i2c_smbus_write_word_data(stdp4028_i2c, >>> + STDP4028_DPTX_IRQ_STS_REG, >>> + STDP4028_DPTX_IRQ_CLEAR); >>> + >>> + if (ge_b850v3_lvds_ptr->connector.dev) >>> + drm_kms_helper_hotplug_event(ge_b850v3_lvds_ptr->connector.dev); >>> + >>> + return IRQ_HANDLED; >>> +} >>> + >>> +static int ge_b850v3_lvds_attach(struct drm_bridge *bridge) >>> +{ >>> + struct drm_connector *connector = &ge_b850v3_lvds_ptr->connector; >>> + struct i2c_client *stdp4028_i2c >>> + = ge_b850v3_lvds_ptr->stdp4028_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_connector_helper_funcs); >>> + >>> + ret = drm_connector_init(bridge->dev, connector, >>> + &ge_b850v3_lvds_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; >>> + >>> + /* Configures the bridge to re-enable interrupts after each ack. */ >>> + i2c_smbus_write_word_data(stdp4028_i2c, >>> + STDP4028_IRQ_OUT_CONF_REG, >>> + STDP4028_DPTX_DP_IRQ_EN); >>> + >>> + /* Enable interrupts */ >>> + i2c_smbus_write_word_data(stdp4028_i2c, >>> + STDP4028_DPTX_IRQ_EN_REG, >>> + STDP4028_DPTX_IRQ_CONFIG); >>> + >>> + return 0; >>> +} >>> + >>> +static const struct drm_bridge_funcs ge_b850v3_lvds_funcs = { >>> + .attach = ge_b850v3_lvds_attach, >>> +}; >>> + >>> +static int ge_b850v3_lvds_init(struct device *dev) >>> +{ >>> + mutex_lock(&ge_b850v3_lvds_dev_mutex); >>> + >>> + if (ge_b850v3_lvds_ptr) >>> + goto success; >>> + >>> + ge_b850v3_lvds_ptr = devm_kzalloc(dev, >>> + sizeof(*ge_b850v3_lvds_ptr), >>> + GFP_KERNEL); >>> + >>> + if (!ge_b850v3_lvds_ptr) { >>> + mutex_unlock(&ge_b850v3_lvds_dev_mutex); >>> + return -ENOMEM; >>> + } >>> + >>> + ge_b850v3_lvds_ptr->bridge.funcs = &ge_b850v3_lvds_funcs; >>> + ge_b850v3_lvds_ptr->bridge.of_node = dev->of_node; >>> + drm_bridge_add(&ge_b850v3_lvds_ptr->bridge); >>> + >>> +success: >>> + mutex_unlock(&ge_b850v3_lvds_dev_mutex); >>> + return 0; >>> +} >>> + >>> +static void ge_b850v3_lvds_remove(void) >>> +{ >>> + mutex_lock(&ge_b850v3_lvds_dev_mutex); >>> + /* >>> + * This check is to avoid both the drivers >>> + * removing the bridge in their remove() function >>> + */ >>> + if (!ge_b850v3_lvds_ptr) >>> + goto out; >>> + >>> + drm_bridge_remove(&ge_b850v3_lvds_ptr->bridge); >>> + >>> + kfree(ge_b850v3_lvds_ptr->edid); >>> + >>> + ge_b850v3_lvds_ptr = NULL; >>> +out: >>> + mutex_unlock(&ge_b850v3_lvds_dev_mutex); >>> +} >>> + >>> +static int stdp4028_ge_b850v3_fw_probe(struct i2c_client *stdp4028_i2c, >>> + const struct i2c_device_id *id) >>> +{ >>> + struct device *dev = &stdp4028_i2c->dev; >>> + >>> + ge_b850v3_lvds_init(dev); >>> + >>> + ge_b850v3_lvds_ptr->stdp4028_i2c = stdp4028_i2c; >>> + i2c_set_clientdata(stdp4028_i2c, ge_b850v3_lvds_ptr); >>> + >>> + /* Clear pending interrupts since power up. */ >>> + i2c_smbus_write_word_data(stdp4028_i2c, >>> + STDP4028_DPTX_IRQ_STS_REG, >>> + STDP4028_DPTX_IRQ_CLEAR); >>> + >>> + if (!stdp4028_i2c->irq) >>> + return 0; >>> + >>> + return devm_request_threaded_irq(&stdp4028_i2c->dev, >>> + stdp4028_i2c->irq, NULL, >>> + ge_b850v3_lvds_irq_handler, >>> + IRQF_TRIGGER_HIGH | IRQF_ONESHOT, >>> + "ge-b850v3-lvds-dp", ge_b850v3_lvds_ptr); >>> +} >>> + >>> +static int stdp4028_ge_b850v3_fw_remove(struct i2c_client *stdp4028_i2c) >>> +{ >>> + ge_b850v3_lvds_remove(); >>> + >>> + return 0; >>> +} >>> + >>> +static const struct i2c_device_id stdp4028_ge_b850v3_fw_i2c_table[] = { >>> + {"stdp4028_ge_fw", 0}, >>> + {}, >>> +}; >>> +MODULE_DEVICE_TABLE(i2c, stdp4028_ge_b850v3_fw_i2c_table); >>> + >>> +static const struct of_device_id stdp4028_ge_b850v3_fw_match[] = { >>> + { .compatible = "megachips,stdp4028-ge-b850v3-fw" }, >>> + {}, >>> +}; >>> +MODULE_DEVICE_TABLE(of, stdp4028_ge_b850v3_fw_match); >>> + >>> +static struct i2c_driver stdp4028_ge_b850v3_fw_driver = { >>> + .id_table = stdp4028_ge_b850v3_fw_i2c_table, >>> + .probe = stdp4028_ge_b850v3_fw_probe, >>> + .remove = stdp4028_ge_b850v3_fw_remove, >>> + .driver = { >>> + .name = "stdp4028-ge-b850v3-fw", >>> + .of_match_table = stdp4028_ge_b850v3_fw_match, >>> + }, >>> +}; >>> +module_i2c_driver(stdp4028_ge_b850v3_fw_driver); >>> + >>> +static int stdp2690_ge_b850v3_fw_probe(struct i2c_client *stdp2690_i2c, >>> + const struct i2c_device_id *id) >>> +{ >>> + struct device *dev = &stdp2690_i2c->dev; >>> + >>> + ge_b850v3_lvds_init(dev); >>> + >>> + ge_b850v3_lvds_ptr->stdp2690_i2c = stdp2690_i2c; >>> + i2c_set_clientdata(stdp2690_i2c, ge_b850v3_lvds_ptr); >>> + >>> + return 0; >>> +} >>> + >>> +static int stdp2690_ge_b850v3_fw_remove(struct i2c_client *stdp2690_i2c) >>> +{ >>> + ge_b850v3_lvds_remove(); >>> + >>> + return 0; >>> +} >>> + >>> +static const struct i2c_device_id stdp2690_ge_b850v3_fw_i2c_table[] = { >>> + {"stdp2690_ge_fw", 0}, >>> + {}, >>> +}; >>> +MODULE_DEVICE_TABLE(i2c, stdp2690_ge_b850v3_fw_i2c_table); >>> + >>> +static const struct of_device_id stdp2690_ge_b850v3_fw_match[] = { >>> + { .compatible = "megachips,stdp2690-ge-b850v3-fw" }, >>> + {}, >>> +}; >>> +MODULE_DEVICE_TABLE(of, stdp2690_ge_b850v3_fw_match); >>> + >>> +static struct i2c_driver stdp2690_ge_b850v3_fw_driver = { >>> + .id_table = stdp2690_ge_b850v3_fw_i2c_table, >>> + .probe = stdp2690_ge_b850v3_fw_probe, >>> + .remove = stdp2690_ge_b850v3_fw_remove, >>> + .driver = { >>> + .name = "stdp2690-ge-b850v3-fw", >>> + .of_match_table = stdp2690_ge_b850v3_fw_match, >>> + }, >>> +}; >>> +module_i2c_driver(stdp2690_ge_b850v3_fw_driver); >> >> Didn't catch this in the last series, but there can only be one >> module_init call per module. This breaks compilation when the >> driver is built as a module. > > Unfortunately yes. Got loads of errors when trying to compile as a > module. > >> >> You could do something like: >> >> static int __init stdpxxxx_ge_b850v3_init(void) >> { >> int ret; >> >> ret = i2c_add_driver(&stdp4028_ge_b850v3_fw_driver); >> if (ret) >> return ret; >> >> return i2c_add_driver(&stdp2690_ge_b850v3_fw_driver); >> } >> module_init(stdpxxxx_ge_b850v3_init); >> >> static void __exit stdpxxxx_ge_b850v3_exit(void) >> { >> i2c_del_driver(&stdp2690_ge_b850v3_fw_driver); >> i2c_del_driver(&stdp4028_ge_b850v3_fw_driver); >> } >> module_exit(stdpxxxx_ge_b850v3_exit); > > Thank you! I was wondering if merging ge_b850v3_lvds_init() with > stdpxxxx_ge_b850v3_init() and ge_b850v3_lvds_remove() with > stdpxxxx_ge_b850v3_exit() make sense as it can probably eliminate the > need for the mutex. Doing anything apart from the driver registration/unregistration in the module_init/exit calls is frowned upon. Nothing specific to the device should ideally be added in them. It would be nice to eventually get rid of the lvds_dev_mutex, but I think we can live with it for now. Regards, Archit -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation