Hi, Some comments.
On 08/09/2016 10:11 PM, Peter Senna Tschudin wrote: > Add a driver that create 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 hardware and > firmware made it complicated for this binding to comprise two device > tree nodes, as the design goal is to configure both bridges based on > the LVDS signal, which leave the driver powerless to control the video > processing pipeline. The two bridges behaves as a single bridge, and > the driver is only needed for telling the host about EDID / HPD, and > for giving the host powers to ack interrupts. The video signal pipeline > is as follows: > > Host -> LVDS|--(STDP4028)--|DP -> DP|--(STDP2690)--|DP++ -> Video output > > Cc: Martyn Welch <martyn.welch at collabora.co.uk> > Cc: Martin Donnelly <martin.donnelly at ge.com> > Cc: Daniel Vetter <daniel.vetter at ffwll.ch> > Cc: Enric Balletbo i Serra <enric.balletbo at collabora.com> > Cc: Philipp Zabel <p.zabel at pengutronix.de> > Cc: Rob Herring <robh at kernel.org> > Cc: Fabio Estevam <fabio.estevam at nxp.com> > CC: David Airlie <airlied at linux.ie> > CC: Thierry Reding <treding at nvidia.com> > CC: Thierry Reding <thierry.reding at gmail.com> > Reviewed-by: Enric Balletbo <enric.balletbo at collabora.com> > Signed-off-by: Peter Senna Tschudin <peter.senna at collabora.com> > --- > Changes from V4: > - Check the output of the first call to i2c_smbus_write_word_data() and > return > it's error code for failing gracefully on i2c issues > - Renamed the i2c_driver.name from "ge,b850v3-lvds-dp" to "b850v3-lvds-dp" to > remove the comma from the driver name > > Changes from V3: > - 3/4 instead of 4/5 > - Tested on next-20160804 > > Changes from V2: > - Made it atomic to be applied on next-20160729 on top of Liu Ying changes > that made imx-ldb atomic > > Changes from V1: > - New commit message > - Removed 3 empty entry points > - Removed memory leak from ge_b850v3_lvds_dp_get_modes() > - Added a lock for mode setting > - Removed a few blank lines > - Changed the order at Makefile and Kconfig > > MAINTAINERS | 8 + > drivers/gpu/drm/bridge/Kconfig | 11 + > drivers/gpu/drm/bridge/Makefile | 1 + > drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c | 405 > +++++++++++++++++++++++++++++ > 4 files changed, 425 insertions(+) > create mode 100644 drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index a306795..e8d106a 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -5142,6 +5142,14 @@ W: https://linuxtv.org > S: Maintained > F: drivers/media/radio/radio-gemtek* > > +GENERAL ELECTRIC B850V3 LVDS/DP++ BRIDGE > +M: Peter Senna Tschudin <peter.senna at collabora.com> > +M: Martin Donnelly <martin.donnelly at ge.com> > +M: Martyn Welch <martyn.welch at collabora.co.uk> > +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 <hskinnemoen at gmail.com> > S: Supported Could you move the MAINTAINERS change to a different patch? It would make it easier to integrate separately. > diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig > index b590e67..b4b70fb 100644 > --- a/drivers/gpu/drm/bridge/Kconfig > +++ b/drivers/gpu/drm/bridge/Kconfig > @@ -32,6 +32,17 @@ config DRM_DW_HDMI_AHB_AUDIO > Designware HDMI block. This is used in conjunction with > the i.MX6 HDMI driver. > > +config DRM_GE_B850V3_LVDS_DP > + tristate "GE B850v3 LVDS to DP++ display bridge" > + depends on OF > + select DRM_KMS_HELPER > + select DRM_PANEL > + ---help--- > + This is a driver for the display bridge of > + GE B850v3 that convert dual channel LVDS > + to DP++. This is used with the i.MX6 imx-ldb > + driver. > + > 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 efdb07e..b9606f3 100644 > --- a/drivers/gpu/drm/bridge/Makefile > +++ b/drivers/gpu/drm/bridge/Makefile > @@ -3,6 +3,7 @@ ccflags-y := -Iinclude/drm > obj-$(CONFIG_DRM_ANALOGIX_ANX78XX) += analogix-anx78xx.o > obj-$(CONFIG_DRM_DW_HDMI) += dw-hdmi.o > obj-$(CONFIG_DRM_DW_HDMI_AHB_AUDIO) += dw-hdmi-ahb-audio.o > +obj-$(CONFIG_DRM_GE_B850V3_LVDS_DP) += ge_b850v3_lvds_dp.o > obj-$(CONFIG_DRM_NXP_PTN3460) += nxp-ptn3460.o > obj-$(CONFIG_DRM_PARADE_PS8622) += parade-ps8622.o > obj-$(CONFIG_DRM_SII902X) += sii902x.o > 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..81e9279 > --- /dev/null > +++ b/drivers/gpu/drm/bridge/ge_b850v3_lvds_dp.c > @@ -0,0 +1,405 @@ > +/* > + * 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 <http://www.gnu.org/licenses/>. > + > + * 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 <linux/gpio.h> > +#include <linux/i2c.h> > +#include <linux/module.h> > +#include <linux/of.h> > +#include <drm/drm_atomic.h> > +#include <drm/drm_atomic_helper.h> > +#include <drm/drm_crtc_helper.h> > +#include <drm/drm_edid.h> > +#include <drm/drmP.h> > + > +/* > + * 220Mhz is a limitation of the host, as the bridge is capable of up to > + * 330Mhz. See section 9.2.1.2.4 of the i.MX 6Dual/6Quad Applications > + * Processor Reference Manual for more information about the 220Mhz limit. > + * The imx-ldb driver will warn about clocks over 170Mhz, but it seem to work > + * fine. > + */ > +#define MAX_PIXEL_CLOCK 220000 > + > +#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; > + struct mutex lock; > +}; > + > +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); > +} > + > +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; > + int num_modes = 0; > + > + ptn_bridge = connector_to_ge_b850v3_lvds_dp(connector); > + client = ptn_bridge->edid_i2c; > + > + mutex_lock(&ptn_bridge->lock); > + > + kfree(ptn_bridge->edid); > + ptn_bridge->edid = (struct edid *) stdp2690_get_edid(client); > + > + if (ptn_bridge->edid) { > + drm_mode_connector_update_edid_property(connector, > + ptn_bridge->edid); > + num_modes = drm_add_edid_modes(connector, ptn_bridge->edid); > + } > + > + mutex_unlock(&ptn_bridge->lock); > + > + return num_modes; > +} > + > + > +static enum drm_mode_status ge_b850v3_lvds_dp_mode_valid( > + struct drm_connector *connector, struct drm_display_mode *mode) > +{ > + if (mode->clock > MAX_PIXEL_CLOCK) { > + DRM_INFO("The pixel clock for the mode %s is too high, and not > supported.", > + mode->name); > + return MODE_CLOCK_HIGH; > + } > + > + return MODE_OK; > +} > + > +static const struct > +drm_connector_helper_funcs ge_b850v3_lvds_dp_connector_helper_funcs = { > + .get_modes = ge_b850v3_lvds_dp_get_modes, > + .mode_valid = ge_b850v3_lvds_dp_mode_valid, > +}; > + > +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 const struct drm_connector_funcs ge_b850v3_lvds_dp_connector_funcs = { > + .dpms = drm_atomic_helper_connector_dpms, > + .fill_modes = drm_helper_probe_single_connector_modes, > + .detect = ge_b850v3_lvds_dp_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_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; > + > + mutex_lock(&ptn_bridge->lock); > + > + i2c_smbus_write_word_data(ge_b850v3_lvds_dp_i2c, > + STDP4028_DPTX_IRQ_STS_REG, STDP4028_DPTX_IRQ_CLEAR); > + > + mutex_unlock(&ptn_bridge->lock); > + > + if (ptn_bridge->connector.dev) > + drm_kms_helper_hotplug_event(ptn_bridge->connector.dev); > + > + return IRQ_HANDLED; > +} > + > +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; > + } > + > + drm_connector_register(connector); Connectors shouldn't be registered in the bridge driver, they should be registered by the kms driver after drm_dev_register is called. The drm_connector_register_all() API is used for that. > + ret = drm_mode_connector_attach_encoder(connector, bridge->encoder); > + if (ret) > + return ret; > + > + drm_bridge_enable(bridge); This drm_bridge_enable() doesn't seem to serve any purpose here. It also doesn't seem to make much sense to call drm_bridge_() funcs within a bridge op itself. > + 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); Is there a reason why we register the interrupt handler here and not in probe? Thanks, Archit -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project
