[PATCH 4/8] video: atmel_lcdfb: add device tree suport
Jean-Christophe PLAGNIOL-VILLARD
plagnioj at jcrosoft.com
Fri Apr 12 01:00:18 EST 2013
get display timings from device tree
Use videomode helpers to get display timings and configurations from
device tree
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
Cc: linux-fbdev at vger.kernel.org
Cc: Nicolas Ferre <nicolas.ferre at atmel.com>
Cc: Andrew Morton <akpm at linux-foundation.org>
---
.../devicetree/bindings/video/atmel,lcdc.txt | 75 ++++++
drivers/video/Kconfig | 2 +
drivers/video/atmel_lcdfb.c | 244 +++++++++++++++++---
3 files changed, 289 insertions(+), 32 deletions(-)
create mode 100644 Documentation/devicetree/bindings/video/atmel,lcdc.txt
diff --git a/Documentation/devicetree/bindings/video/atmel,lcdc.txt b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
new file mode 100644
index 0000000..1ec175e
--- /dev/null
+++ b/Documentation/devicetree/bindings/video/atmel,lcdc.txt
@@ -0,0 +1,75 @@
+Atmel LCDC Framebuffer
+-----------------------------------------------------
+
+Required properties:
+- compatible :
+ "atmel,at91sam9261-lcdc" ,
+ "atmel,at91sam9263-lcdc" ,
+ "atmel,at91sam9g10-lcdc" ,
+ "atmel,at91sam9g45-lcdc" ,
+ "atmel,at91sam9g45es-lcdc" ,
+ "atmel,at91sam9rl-lcdc" ,
+ "atmel,at32ap-lcdc"
+- reg : Should contain 1 register ranges(address and length)
+- interrupts : framebuffer controller interrupt
+- display: a phandle pointing to the display node
+
+Required nodes:
+- display: a display node is required to initialize the lcd panel
+ This should be in the board dts.
+- default-mode: a videomode within the display with timing parameters
+ as specified below.
+
+Example:
+
+ fb0: fb at 0x00500000 {
+ compatible = "atmel,at91sam9g45-lcdc";
+ reg = <0x00500000 0x1000>;
+ interrupts = <23 3 0>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_fb>;
+ display = <&display0>;
+ status = "okay";
+ #address-cells = <1>;
+ #size-cells = <1>;
+
+ };
+
+Atmel LCDC Display
+-----------------------------------------------------
+Required properties (as per of_videomode_helper):
+
+ - atmel,dmacon: dma controler configuration
+ - atmel,lcdcon2: lcd controler configuration
+ - atmel,guard-time: lcd guard time (Delay in frame periods)
+ - bits-per-pixel: lcd panel bit-depth.
+
+Optional properties (as per of_videomode_helper):
+ - atmel,lcdcon-backlight: enable backlight
+ - atmel,lcd-wiring-mode: lcd wiring mode "RGB" or "BRG"
+ - atmel,power-control-gpio: gpio to power on or off the LCD (as many as needed)
+
+Example:
+ display0: display {
+ bits-per-pixel = <32>;
+ atmel,lcdcon-backlight;
+ atmel,dmacon = <0x1>;
+ atmel,lcdcon2 = <0x80008002>;
+ atmel,guard-time = <9>;
+ atmel,lcd-wiring-mode = <1>;
+
+ display-timings {
+ native-mode = <&timing0>;
+ timing0: timing0 {
+ clock-frequency = <9000000>;
+ hactive = <480>;
+ vactive = <272>;
+ hback-porch = <1>;
+ hfront-porch = <1>;
+ vback-porch = <40>;
+ vfront-porch = <1>;
+ hsync-len = <45>;
+ vsync-len = <1>;
+ };
+ };
+ };
diff --git a/drivers/video/Kconfig b/drivers/video/Kconfig
index 4c1546f..0687482 100644
--- a/drivers/video/Kconfig
+++ b/drivers/video/Kconfig
@@ -1018,6 +1018,8 @@ config FB_ATMEL
select FB_CFB_FILLRECT
select FB_CFB_COPYAREA
select FB_CFB_IMAGEBLIT
+ select FB_MODE_HELPERS
+ select OF_VIDEOMODE
help
This enables support for the AT91/AT32 LCD Controller.
diff --git a/drivers/video/atmel_lcdfb.c b/drivers/video/atmel_lcdfb.c
index f67e226..4a31570 100644
--- a/drivers/video/atmel_lcdfb.c
+++ b/drivers/video/atmel_lcdfb.c
@@ -20,7 +20,11 @@
#include <linux/gfp.h>
#include <linux/module.h>
#include <linux/platform_data/atmel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_gpio.h>
#include <video/of_display_timing.h>
+#include <video/videomode.h>
#include <mach/cpu.h>
#include <asm/gpio.h>
@@ -59,6 +63,13 @@ struct atmel_lcdfb_info {
struct atmel_lcdfb_config *config;
};
+struct atmel_lcdfb_power_ctrl_gpio {
+ int gpio;
+ int active_low;
+
+ struct list_head list;
+};
+
#define lcdc_readl(sinfo, reg) __raw_readl((sinfo)->mmio+(reg))
#define lcdc_writel(sinfo, reg, val) __raw_writel((val), (sinfo)->mmio+(reg))
@@ -945,16 +956,187 @@ static void atmel_lcdfb_stop_clock(struct atmel_lcdfb_info *sinfo)
clk_disable(sinfo->lcdc_clk);
}
+#ifdef CONFIG_OF
+static const struct of_device_id atmel_lcdfb_dt_ids[] = {
+ { .compatible = "atmel,at91sam9261-lcdc" , .data = &at91sam9261_config, },
+ { .compatible = "atmel,at91sam9263-lcdc" , .data = &at91sam9263_config, },
+ { .compatible = "atmel,at91sam9g10-lcdc" , .data = &at91sam9g10_config, },
+ { .compatible = "atmel,at91sam9g45-lcdc" , .data = &at91sam9g45_config, },
+ { .compatible = "atmel,at91sam9g45es-lcdc" , .data = &at91sam9g45es_config, },
+ { .compatible = "atmel,at91sam9rl-lcdc" , .data = &at91sam9rl_config, },
+ { .compatible = "atmel,at32ap-lcdc" , .data = &at32ap_config, },
+ { /* sentinel */ }
+};
+
+MODULE_DEVICE_TABLE(of, atmel_lcdfb_dt_ids);
+
+static const char *atmel_lcdfb_wiring_modes[] = {
+ [ATMEL_LCDC_WIRING_BGR] = "BRG",
+ [ATMEL_LCDC_WIRING_RGB] = "RGB",
+};
+
+const int atmel_lcdfb_get_of_wiring_modes(struct device_node *np)
+{
+ const char *mode;
+ int err, i;
+
+ err = of_property_read_string(np, "atmel,lcd-wiring-mode", &mode);
+ if (err < 0)
+ return ATMEL_LCDC_WIRING_BGR;
+
+ for (i = 0; i < ARRAY_SIZE(atmel_lcdfb_wiring_modes); i++)
+ if (!strcasecmp(mode, atmel_lcdfb_wiring_modes[i]))
+ return i;
+
+ return -ENODEV;
+}
+
+static void atmel_lcdfb_power_control_gpio(struct atmel_lcdfb_pdata *pdata, int on)
+{
+ struct atmel_lcdfb_power_ctrl_gpio *og;
+
+ list_for_each_entry(og, &pdata->pwr_gpios, list)
+ gpio_set_value(og->gpio, on);
+}
+
+static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
+{
+ struct fb_info *info = sinfo->info;
+ struct atmel_lcdfb_pdata *pdata = &sinfo->pdata;
+ struct fb_var_screeninfo *var = &info->var;
+ struct device *dev = &sinfo->pdev->dev;
+ struct device_node *np =dev->of_node;
+ struct device_node *display_np;
+ struct device_node *timings_np;
+ struct display_timings *timings;
+ enum of_gpio_flags flags;
+ struct atmel_lcdfb_power_ctrl_gpio *og;
+ bool is_gpio_power = false;
+ int ret = -ENOENT;
+ int i, gpio;
+
+ sinfo->config = (struct atmel_lcdfb_config*)
+ of_match_device(atmel_lcdfb_dt_ids, dev)->data;
+
+ display_np = of_parse_phandle(np, "display", 0);
+ if (!display_np) {
+ dev_err(dev, "failed to find display phandle\n");
+ return -ENOENT;
+ }
+
+ ret = of_property_read_u32(display_np, "bits-per-pixel", &var->bits_per_pixel);
+ if (ret < 0) {
+ dev_err(dev, "failed to get property bits-per-pixel\n");
+ goto put_display_node;
+ }
+
+ ret = of_property_read_u32(display_np, "atmel,guard-time", &pdata->guard_time);
+ if (ret < 0) {
+ dev_err(dev, "failed to get property atmel,guard-time\n");
+ goto put_display_node;
+ }
+
+ ret = of_property_read_u32(display_np, "atmel,lcdcon2", &pdata->default_lcdcon2);
+ if (ret < 0) {
+ dev_err(dev, "failed to get property atmel,lcdcon2\n");
+ goto put_display_node;
+ }
+
+ ret = of_property_read_u32(display_np, "atmel,dmacon", &pdata->default_dmacon);
+ if (ret < 0) {
+ dev_err(dev, "failed to get property bits-per-pixel\n");
+ goto put_display_node;
+ }
+
+ ret = -ENOMEM;
+ for (i = 0; i < of_gpio_named_count(display_np, "atmel,power-control-gpio"); i++) {
+ gpio = of_get_named_gpio_flags(display_np, "atmel,power-control-gpio",
+ i, &flags);
+ if (gpio < 0)
+ continue;
+
+ og = devm_kzalloc(dev, sizeof(*og), GFP_KERNEL);
+ if (!og)
+ goto put_display_node;
+
+ og->gpio = gpio;
+ og->active_low = flags & OF_GPIO_ACTIVE_LOW;
+ is_gpio_power = true;
+ ret = devm_gpio_request(dev, gpio, "lcd-power-control-gpio");
+ if (ret) {
+ dev_err(dev, "request gpio %d failed\n", gpio);
+ goto put_display_node;
+ }
+
+ ret = gpio_direction_output(gpio, og->active_low);
+ if (ret) {
+ dev_err(dev, "set direction output gpio %d failed\n", gpio);
+ goto put_display_node;
+ }
+ }
+
+ if (is_gpio_power)
+ pdata->atmel_lcdfb_power_control = atmel_lcdfb_power_control_gpio;
+
+ ret = atmel_lcdfb_get_of_wiring_modes(display_np);
+ if (ret < 0) {
+ dev_err(dev, "invalid atmel,lcd-wiring-mode\n");
+ goto put_display_node;
+ }
+ pdata->lcd_wiring_mode = ret;
+
+ pdata->lcdcon_is_backlight = of_property_read_bool(display_np, "atmel,lcdcon-backlight");
+
+ timings = of_get_display_timings(display_np);
+ if (!timings) {
+ dev_err(dev, "failed to get display timings\n");
+ goto put_display_node;
+ }
+
+ timings_np = of_find_node_by_name(display_np, "display-timings");
+ if (!timings_np) {
+ dev_err(dev, "failed to find display-timings node\n");
+ goto put_display_node;
+ }
+
+ for (i = 0; i < of_get_child_count(timings_np); i++) {
+ struct videomode vm;
+ struct fb_videomode fb_vm;
+
+ ret = videomode_from_timing(timings, &vm, i);
+ if (ret < 0)
+ goto put_timings_node;
+ ret = fb_videomode_from_videomode(&vm, &fb_vm);
+ if (ret < 0)
+ goto put_timings_node;
+
+ fb_add_videomode(&fb_vm, &info->modelist);
+ }
+
+ return 0;
+
+put_timings_node:
+ of_node_put(timings_np);
+put_display_node:
+ of_node_put(display_np);
+ return ret;
+}
+#else
+static int atmel_lcdfb_of_init(struct atmel_lcdfb_info *sinfo)
+{
+ return 0;
+}
+#endif
static int __init atmel_lcdfb_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct fb_info *info;
struct atmel_lcdfb_info *sinfo;
- struct atmel_lcdfb_pdata *pdata;
- struct fb_videomode fbmode;
+ struct atmel_lcdfb_pdata *pdata = NULL;
struct resource *regs = NULL;
struct resource *map = NULL;
+ struct fb_modelist *modelist;
int ret;
dev_dbg(dev, "%s BEGIN\n", __func__);
@@ -967,17 +1149,35 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
}
sinfo = info->par;
+ sinfo->pdev = pdev;
+ sinfo->info = info;
+
+ INIT_LIST_HEAD(&info->modelist);
- if (dev->platform_data) {
- pdata = (struct atmel_lcdfb_pdata *)dev->platform_data;
+ if (pdev->dev.of_node) {
+ ret = atmel_lcdfb_of_init(sinfo);
+ if (ret)
+ goto free_info;
+ } else if (dev->platform_data) {
+ struct fb_monspecs *monspecs;
+ int i;
+
+ pdata = dev->platform_data;
+ monspecs = pdata->default_monspecs;
sinfo->pdata = *pdata;
+
+ for (i = 0; i < monspecs->modedb_len; i++)
+ fb_add_videomode(&monspecs->modedb[i], &info->modelist);
+
+ sinfo->config = atmel_lcdfb_get_config(pdev);
+
+ info->var.bits_per_pixel = pdata->default_bpp ? pdata->default_bpp : 16;
+ memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
} else {
dev_err(dev, "cannot get default configuration\n");
goto free_info;
}
- sinfo->info = info;
- sinfo->pdev = pdev;
- sinfo->config = atmel_lcdfb_get_config(pdev);
+
if (!sinfo->config)
goto free_info;
@@ -986,7 +1186,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
info->pseudo_palette = sinfo->pseudo_palette;
info->fbops = &atmel_lcdfb_ops;
- memcpy(&info->monspecs, pdata->default_monspecs, sizeof(info->monspecs));
info->fix = atmel_lcdfb_fix;
/* Enable LCDC Clocks */
@@ -1002,14 +1201,11 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
}
atmel_lcdfb_start_clock(sinfo);
- ret = fb_find_mode(&info->var, info, NULL, info->monspecs.modedb,
- info->monspecs.modedb_len, info->monspecs.modedb,
- pdata->default_bpp);
- if (!ret) {
- dev_err(dev, "no suitable video mode found\n");
- goto stop_clk;
- }
+ modelist = list_first_entry(&info->modelist,
+ struct fb_modelist, list);
+ fb_videomode_to_var(&info->var, &modelist->mode);
+ atmel_lcdfb_check_var(&info->var, info);
regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!regs) {
@@ -1093,18 +1289,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
goto unregister_irqs;
}
- /*
- * This makes sure that our colour bitfield
- * descriptors are correctly initialised.
- */
- atmel_lcdfb_check_var(&info->var, info);
-
- ret = fb_set_var(info, &info->var);
- if (ret) {
- dev_warn(dev, "unable to set display parameters\n");
- goto free_cmap;
- }
-
dev_set_drvdata(dev, info);
/*
@@ -1116,10 +1300,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
goto reset_drvdata;
}
- /* add selected videomode to modelist */
- fb_var_to_videomode(&fbmode, &info->var);
- fb_add_videomode(&fbmode, &info->modelist);
-
/* Power up the LCDC screen */
atmel_lcdfb_power_control(sinfo, 1);
@@ -1130,7 +1310,6 @@ static int __init atmel_lcdfb_probe(struct platform_device *pdev)
reset_drvdata:
dev_set_drvdata(dev, NULL);
-free_cmap:
fb_dealloc_cmap(&info->cmap);
unregister_irqs:
cancel_work_sync(&sinfo->task);
@@ -1249,6 +1428,7 @@ static struct platform_driver atmel_lcdfb_driver = {
.driver = {
.name = "atmel_lcdfb",
.owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(atmel_lcdfb_dt_ids),
},
};
--
1.7.10.4
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