lkml.org 
[lkml]   [2013]   [Oct]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 3/5] drm/bridge: Add PTN3460 bridge driver
    Date
    This patch adds a drm_bridge driver for the PTN3460 DisplayPort to LVDS
    bridge chip.

    Signed-off-by: Sean Paul <seanpaul@chromium.org>
    ---
    .../devicetree/bindings/drm/bridge/ptn3460.txt | 27 ++
    drivers/gpu/drm/Kconfig | 2 +
    drivers/gpu/drm/Makefile | 1 +
    drivers/gpu/drm/bridge/Kconfig | 4 +
    drivers/gpu/drm/bridge/Makefile | 3 +
    drivers/gpu/drm/bridge/ptn3460.c | 349 +++++++++++++++++++++
    include/drm/bridge/ptn3460.h | 36 +++
    7 files changed, 422 insertions(+)
    create mode 100644 Documentation/devicetree/bindings/drm/bridge/ptn3460.txt
    create mode 100644 drivers/gpu/drm/bridge/Kconfig
    create mode 100644 drivers/gpu/drm/bridge/Makefile
    create mode 100644 drivers/gpu/drm/bridge/ptn3460.c
    create mode 100644 include/drm/bridge/ptn3460.h

    diff --git a/Documentation/devicetree/bindings/drm/bridge/ptn3460.txt b/Documentation/devicetree/bindings/drm/bridge/ptn3460.txt
    new file mode 100644
    index 0000000..c1cd329
    --- /dev/null
    +++ b/Documentation/devicetree/bindings/drm/bridge/ptn3460.txt
    @@ -0,0 +1,27 @@
    +ptn3460-bridge bindings
    +
    +Required properties:
    + - compatible: "nxp,ptn3460"
    + - reg: i2c address of the bridge
    + - powerdown-gpio: OF device-tree gpio specification
    + - reset-gpio: OF device-tree gpio specification
    + - edid-emulation: The EDID emulation entry to use
    + +-------+------------+------------------+
    + | Value | Resolution | Description |
    + | 0 | 1024x768 | NXP Generic |
    + | 1 | 1920x1080 | NXP Generic |
    + | 2 | 1920x1080 | NXP Generic |
    + | 3 | 1600x900 | Samsung LTM200KT |
    + | 4 | 1920x1080 | Samsung LTM230HT |
    + | 5 | 1366x768 | NXP Generic |
    + | 6 | 1600x900 | ChiMei M215HGE |
    + +-------+------------+------------------+
    +
    +Example:
    + ptn3460-bridge@20 {
    + compatible = "nxp,ptn3460";
    + reg = <0x20>;
    + powerdown-gpio = <&gpy2 5 1 0 0>;
    + reset-gpio = <&gpx1 5 1 0 0>;
    + edid-emulation = <5>;
    + };
    diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
    index 955555d..cd7bfb3 100644
    --- a/drivers/gpu/drm/Kconfig
    +++ b/drivers/gpu/drm/Kconfig
    @@ -236,3 +236,5 @@ source "drivers/gpu/drm/tilcdc/Kconfig"
    source "drivers/gpu/drm/qxl/Kconfig"

    source "drivers/gpu/drm/msm/Kconfig"
    +
    +source "drivers/gpu/drm/bridge/Kconfig"
    diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
    index f089adf..9234253 100644
    --- a/drivers/gpu/drm/Makefile
    +++ b/drivers/gpu/drm/Makefile
    @@ -56,3 +56,4 @@ obj-$(CONFIG_DRM_TILCDC) += tilcdc/
    obj-$(CONFIG_DRM_QXL) += qxl/
    obj-$(CONFIG_DRM_MSM) += msm/
    obj-y += i2c/
    +obj-y += bridge/
    diff --git a/drivers/gpu/drm/bridge/Kconfig b/drivers/gpu/drm/bridge/Kconfig
    new file mode 100644
    index 0000000..f8db069
    --- /dev/null
    +++ b/drivers/gpu/drm/bridge/Kconfig
    @@ -0,0 +1,4 @@
    +config DRM_PTN3460
    + tristate "PTN3460 DP/LVDS bridge"
    + depends on DRM && I2C
    + ---help---
    diff --git a/drivers/gpu/drm/bridge/Makefile b/drivers/gpu/drm/bridge/Makefile
    new file mode 100644
    index 0000000..b4733e1
    --- /dev/null
    +++ b/drivers/gpu/drm/bridge/Makefile
    @@ -0,0 +1,3 @@
    +ccflags-y := -Iinclude/drm
    +
    +obj-$(CONFIG_DRM_PTN3460) += ptn3460.o
    diff --git a/drivers/gpu/drm/bridge/ptn3460.c b/drivers/gpu/drm/bridge/ptn3460.c
    new file mode 100644
    index 0000000..a9e5c1a
    --- /dev/null
    +++ b/drivers/gpu/drm/bridge/ptn3460.c
    @@ -0,0 +1,349 @@
    +/*
    + * NXP PTN3460 DP/LVDS bridge driver
    + *
    + * Copyright (C) 2013 Google, Inc.
    + *
    + * This software is licensed under the terms of the GNU General Public
    + * License version 2, as published by the Free Software Foundation, and
    + * may be copied, distributed, and modified under those terms.
    + *
    + * This program is distributed in the hope that 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.
    + */
    +
    +#include <linux/module.h>
    +#include <linux/of.h>
    +#include <linux/of_gpio.h>
    +#include <linux/i2c.h>
    +#include <linux/gpio.h>
    +#include <linux/delay.h>
    +
    +#include "drmP.h"
    +#include "drm_edid.h"
    +#include "drm_crtc.h"
    +#include "drm_crtc_helper.h"
    +
    +#include "bridge/ptn3460.h"
    +
    +#define PTN3460_EDID_ADDR 0x0
    +#define PTN3460_EDID_EMULATION_ADDR 0x84
    +#define PTN3460_EDID_ENABLE_EMULATION 0
    +#define PTN3460_EDID_EMULATION_SELECTION 1
    +#define PTN3460_EDID_SRAM_LOAD_ADDR 0x85
    +
    +struct ptn3460_bridge {
    + struct drm_connector connector;
    + struct i2c_client *client;
    + struct drm_encoder *encoder;
    + struct drm_bridge *bridge;
    + struct edid *edid;
    + int gpio_pd_n;
    + int gpio_rst_n;
    + u32 edid_emulation;
    + bool enabled;
    +};
    +
    +static int ptn3460_read_bytes(struct ptn3460_bridge *ptn_bridge, char addr,
    + u8 *buf, int len)
    +{
    + int ret;
    +
    + ret = i2c_master_send(ptn_bridge->client, &addr, 1);
    + if (ret <= 0) {
    + DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
    + return ret;
    + }
    +
    + ret = i2c_master_recv(ptn_bridge->client, buf, len);
    + if (ret <= 0) {
    + DRM_ERROR("Failed to recv i2c data, ret=%d\n", ret);
    + return ret;
    + }
    +
    + return 0;
    +}
    +
    +static int ptn3460_write_byte(struct ptn3460_bridge *ptn_bridge, char addr,
    + char val)
    +{
    + int ret;
    + char buf[2];
    +
    + buf[0] = addr;
    + buf[1] = val;
    +
    + ret = i2c_master_send(ptn_bridge->client, buf, ARRAY_SIZE(buf));
    + if (ret <= 0) {
    + DRM_ERROR("Failed to send i2c command, ret=%d\n", ret);
    + return ret;
    + }
    +
    + return 0;
    +}
    +
    +static int ptn3460_select_edid(struct ptn3460_bridge *ptn_bridge)
    +{
    + int ret;
    + char val;
    +
    + /* Load the selected edid into SRAM (accessed at PTN3460_EDID_ADDR) */
    + ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_SRAM_LOAD_ADDR,
    + ptn_bridge->edid_emulation);
    + if (ret) {
    + DRM_ERROR("Failed to transfer edid to sram, ret=%d\n", ret);
    + return ret;
    + }
    +
    + /* Enable EDID emulation and select the desired EDID */
    + val = 1 << PTN3460_EDID_ENABLE_EMULATION |
    + ptn_bridge->edid_emulation << PTN3460_EDID_EMULATION_SELECTION;
    +
    + ret = ptn3460_write_byte(ptn_bridge, PTN3460_EDID_EMULATION_ADDR, val);
    + if (ret) {
    + DRM_ERROR("Failed to write edid value, ret=%d\n", ret);
    + return ret;
    + }
    +
    + return 0;
    +}
    +
    +static void ptn3460_pre_enable(struct drm_bridge *bridge)
    +{
    + struct ptn3460_bridge *ptn_bridge = bridge->driver_private;
    + int ret;
    +
    + if (ptn_bridge->enabled)
    + return;
    +
    + if (gpio_is_valid(ptn_bridge->gpio_pd_n))
    + gpio_set_value(ptn_bridge->gpio_pd_n, 1);
    +
    + if (gpio_is_valid(ptn_bridge->gpio_rst_n)) {
    + gpio_set_value(ptn_bridge->gpio_rst_n, 0);
    + udelay(10);
    + gpio_set_value(ptn_bridge->gpio_rst_n, 1);
    + }
    +
    + /*
    + * There's a bug in the PTN chip where it falsely asserts hotplug before
    + * it is fully functional. We're forced to wait for the maximum start up
    + * time specified in the chip's datasheet to make sure we're really up.
    + */
    + msleep(90);
    +
    + ret = ptn3460_select_edid(ptn_bridge);
    + if (ret)
    + DRM_ERROR("Select edid failed ret=%d\n", ret);
    +
    + ptn_bridge->enabled = true;
    +}
    +
    +static void ptn3460_enable(struct drm_bridge *bridge)
    +{
    +}
    +
    +static void ptn3460_disable(struct drm_bridge *bridge)
    +{
    + struct ptn3460_bridge *ptn_bridge = bridge->driver_private;
    +
    + if (!ptn_bridge->enabled)
    + return;
    +
    + ptn_bridge->enabled = false;
    +
    + if (gpio_is_valid(ptn_bridge->gpio_rst_n))
    + gpio_set_value(ptn_bridge->gpio_rst_n, 1);
    +
    + if (gpio_is_valid(ptn_bridge->gpio_pd_n))
    + gpio_set_value(ptn_bridge->gpio_pd_n, 0);
    +}
    +
    +static void ptn3460_post_disable(struct drm_bridge *bridge)
    +{
    +}
    +
    +void ptn3460_bridge_destroy(struct drm_bridge *bridge)
    +{
    + struct ptn3460_bridge *ptn_bridge = bridge->driver_private;
    +
    + drm_bridge_cleanup(bridge);
    + if (gpio_is_valid(ptn_bridge->gpio_pd_n))
    + gpio_free(ptn_bridge->gpio_pd_n);
    + if (gpio_is_valid(ptn_bridge->gpio_rst_n))
    + gpio_free(ptn_bridge->gpio_rst_n);
    + /* Nothing else to free, we've got devm allocated memory */
    +}
    +
    +struct drm_bridge_funcs ptn3460_bridge_funcs = {
    + .pre_enable = ptn3460_pre_enable,
    + .enable = ptn3460_enable,
    + .disable = ptn3460_disable,
    + .post_disable = ptn3460_post_disable,
    + .destroy = ptn3460_bridge_destroy,
    +};
    +
    +int ptn3460_get_modes(struct drm_connector *connector)
    +{
    + struct ptn3460_bridge *ptn_bridge;
    + u8 *edid;
    + int ret, num_modes;
    + bool power_off;
    +
    + ptn_bridge = container_of(connector, struct ptn3460_bridge, connector);
    +
    + if (ptn_bridge->edid)
    + return drm_add_edid_modes(connector, ptn_bridge->edid);
    +
    + power_off = !ptn_bridge->enabled;
    + ptn3460_pre_enable(ptn_bridge->bridge);
    +
    + edid = kmalloc(EDID_LENGTH, GFP_KERNEL);
    + if (!edid) {
    + DRM_ERROR("Failed to allocate edid\n");
    + return 0;
    + }
    +
    + ret = ptn3460_read_bytes(ptn_bridge, PTN3460_EDID_ADDR, edid,
    + EDID_LENGTH);
    + if (ret) {
    + kfree(edid);
    + num_modes = 0;
    + goto out;
    + }
    +
    + ptn_bridge->edid = (struct edid *)edid;
    + drm_mode_connector_update_edid_property(connector, ptn_bridge->edid);
    +
    + num_modes = drm_add_edid_modes(connector, ptn_bridge->edid);
    +
    +out:
    + if (power_off)
    + ptn3460_disable(ptn_bridge->bridge);
    +
    + return num_modes;
    +}
    +
    +static int ptn3460_mode_valid(struct drm_connector *connector,
    + struct drm_display_mode *mode)
    +{
    + return MODE_OK;
    +}
    +
    +struct drm_encoder *ptn3460_best_encoder(struct drm_connector *connector)
    +{
    + struct ptn3460_bridge *ptn_bridge;
    +
    + ptn_bridge = container_of(connector, struct ptn3460_bridge, connector);
    +
    + return ptn_bridge->encoder;
    +}
    +
    +struct drm_connector_helper_funcs ptn3460_connector_helper_funcs = {
    + .get_modes = ptn3460_get_modes,
    + .mode_valid = ptn3460_mode_valid,
    + .best_encoder = ptn3460_best_encoder,
    +};
    +
    +enum drm_connector_status ptn3460_detect(struct drm_connector *connector,
    + bool force)
    +{
    + return connector_status_connected;
    +}
    +
    +void ptn3460_connector_destroy(struct drm_connector *connector)
    +{
    + drm_connector_cleanup(connector);
    +}
    +
    +struct drm_connector_funcs ptn3460_connector_funcs = {
    + .dpms = drm_helper_connector_dpms,
    + .fill_modes = drm_helper_probe_single_connector_modes,
    + .detect = ptn3460_detect,
    + .destroy = ptn3460_connector_destroy,
    +};
    +
    +int ptn3460_init(struct drm_device *dev, struct drm_encoder *encoder,
    + struct i2c_client *client, struct device_node *node)
    +{
    + int ret;
    + struct drm_bridge *bridge;
    + struct ptn3460_bridge *ptn_bridge;
    +
    + bridge = devm_kzalloc(dev->dev, sizeof(*bridge), GFP_KERNEL);
    + if (!bridge) {
    + DRM_ERROR("Failed to allocate drm bridge\n");
    + return -ENOMEM;
    + }
    +
    + ptn_bridge = devm_kzalloc(dev->dev, sizeof(*ptn_bridge), GFP_KERNEL);
    + if (!ptn_bridge) {
    + DRM_ERROR("Failed to allocate ptn bridge\n");
    + return -ENOMEM;
    + }
    +
    + ptn_bridge->client = client;
    + ptn_bridge->encoder = encoder;
    + ptn_bridge->bridge = bridge;
    + ptn_bridge->gpio_pd_n = of_get_named_gpio(node, "powerdown-gpio", 0);
    + if (gpio_is_valid(ptn_bridge->gpio_pd_n)) {
    + ret = gpio_request_one(ptn_bridge->gpio_pd_n,
    + GPIOF_OUT_INIT_HIGH, "PTN3460_PD_N");
    + if (ret) {
    + DRM_ERROR("Request powerdown-gpio failed (%d)\n", ret);
    + return ret;
    + }
    + }
    +
    + ptn_bridge->gpio_rst_n = of_get_named_gpio(node, "reset-gpio", 0);
    + if (gpio_is_valid(ptn_bridge->gpio_rst_n)) {
    + /*
    + * Request the reset pin low to avoid the bridge being
    + * initialized prematurely
    + */
    + ret = gpio_request_one(ptn_bridge->gpio_rst_n,
    + GPIOF_OUT_INIT_LOW, "PTN3460_RST_N");
    + if (ret) {
    + DRM_ERROR("Request reset-gpio failed (%d)\n", ret);
    + gpio_free(ptn_bridge->gpio_pd_n);
    + return ret;
    + }
    + }
    +
    + ret = of_property_read_u32(node, "edid-emulation",
    + &ptn_bridge->edid_emulation);
    + if (ret) {
    + DRM_ERROR("Can't read edid emulation value\n");
    + goto err;
    + }
    +
    + ret = drm_bridge_init(dev, bridge, &ptn3460_bridge_funcs);
    + if (ret) {
    + DRM_ERROR("Failed to initialize bridge with drm\n");
    + goto err;
    + }
    +
    + bridge->driver_private = ptn_bridge;
    + encoder->bridge = bridge;
    +
    + ret = drm_connector_init(dev, &ptn_bridge->connector,
    + &ptn3460_connector_funcs, DRM_MODE_CONNECTOR_LVDS);
    + if (ret) {
    + DRM_ERROR("Failed to initialize connector with drm\n");
    + goto err;
    + }
    + drm_connector_helper_add(&ptn_bridge->connector,
    + &ptn3460_connector_helper_funcs);
    + drm_sysfs_connector_add(&ptn_bridge->connector);
    + drm_mode_connector_attach_encoder(&ptn_bridge->connector, encoder);
    +
    + return 0;
    +
    +err:
    + if (gpio_is_valid(ptn_bridge->gpio_pd_n))
    + gpio_free(ptn_bridge->gpio_pd_n);
    + if (gpio_is_valid(ptn_bridge->gpio_rst_n))
    + gpio_free(ptn_bridge->gpio_rst_n);
    + return ret;
    +}
    diff --git a/include/drm/bridge/ptn3460.h b/include/drm/bridge/ptn3460.h
    new file mode 100644
    index 0000000..157ffa1
    --- /dev/null
    +++ b/include/drm/bridge/ptn3460.h
    @@ -0,0 +1,36 @@
    +/*
    + * Copyright (C) 2013 Google, Inc.
    + *
    + * This software is licensed under the terms of the GNU General Public
    + * License version 2, as published by the Free Software Foundation, and
    + * may be copied, distributed, and modified under those terms.
    + *
    + * This program is distributed in the hope that 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.
    + */
    +
    +#ifndef _DRM_BRIDGE_PTN3460_H_
    +#define _DRM_BRIDGE_PTN3460_H_
    +
    +struct drm_device;
    +struct drm_encoder;
    +struct i2c_client;
    +struct device_node;
    +
    +#ifdef CONFIG_DRM_PTN3460
    +
    +int ptn3460_init(struct drm_device *dev, struct drm_encoder *encoder,
    + struct i2c_client *client, struct device_node *node);
    +#else
    +
    +int ptn3460_init(struct drm_device *dev, struct drm_encoder *encoder,
    + struct i2c_client *client, struct device_node *node)
    +{
    + return 0;
    +}
    +
    +#endif
    +
    +#endif
    --
    1.8.4


    \
     
     \ /
      Last update: 2013-10-02 02:01    [W:4.233 / U:0.108 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site