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path: root/drivers/video/fbdev/amba-clcd-nomadik.c
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Diffstat (limited to 'drivers/video/fbdev/amba-clcd-nomadik.c')
-rw-r--r--drivers/video/fbdev/amba-clcd-nomadik.c259
1 files changed, 259 insertions, 0 deletions
diff --git a/drivers/video/fbdev/amba-clcd-nomadik.c b/drivers/video/fbdev/amba-clcd-nomadik.c
new file mode 100644
index 000000000000..0c06fcaaa6e8
--- /dev/null
+++ b/drivers/video/fbdev/amba-clcd-nomadik.c
@@ -0,0 +1,259 @@
+#include <linux/amba/bus.h>
+#include <linux/amba/clcd.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of.h>
+#include <linux/of_graph.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/mfd/syscon.h>
+#include <linux/regmap.h>
+
+#include "amba-clcd-nomadik.h"
+
+static struct gpio_desc *grestb;
+static struct gpio_desc *scen;
+static struct gpio_desc *scl;
+static struct gpio_desc *sda;
+
+static u8 tpg110_readwrite_reg(bool write, u8 address, u8 outval)
+{
+ int i;
+ u8 inval = 0;
+
+ /* Assert SCEN */
+ gpiod_set_value_cansleep(scen, 1);
+ ndelay(150);
+ /* Hammer out the address */
+ for (i = 5; i >= 0; i--) {
+ if (address & BIT(i))
+ gpiod_set_value_cansleep(sda, 1);
+ else
+ gpiod_set_value_cansleep(sda, 0);
+ ndelay(150);
+ /* Send an SCL pulse */
+ gpiod_set_value_cansleep(scl, 1);
+ ndelay(160);
+ gpiod_set_value_cansleep(scl, 0);
+ ndelay(160);
+ }
+
+ if (write) {
+ /* WRITE */
+ gpiod_set_value_cansleep(sda, 0);
+ } else {
+ /* READ */
+ gpiod_set_value_cansleep(sda, 1);
+ }
+ ndelay(150);
+ /* Send an SCL pulse */
+ gpiod_set_value_cansleep(scl, 1);
+ ndelay(160);
+ gpiod_set_value_cansleep(scl, 0);
+ ndelay(160);
+
+ if (!write)
+ /* HiZ turn-around cycle */
+ gpiod_direction_input(sda);
+ ndelay(150);
+ /* Send an SCL pulse */
+ gpiod_set_value_cansleep(scl, 1);
+ ndelay(160);
+ gpiod_set_value_cansleep(scl, 0);
+ ndelay(160);
+
+ /* Hammer in/out the data */
+ for (i = 7; i >= 0; i--) {
+ int value;
+
+ if (write) {
+ value = !!(outval & BIT(i));
+ gpiod_set_value_cansleep(sda, value);
+ } else {
+ value = gpiod_get_value(sda);
+ if (value)
+ inval |= BIT(i);
+ }
+ ndelay(150);
+ /* Send an SCL pulse */
+ gpiod_set_value_cansleep(scl, 1);
+ ndelay(160);
+ gpiod_set_value_cansleep(scl, 0);
+ ndelay(160);
+ }
+
+ gpiod_direction_output(sda, 0);
+ /* Deassert SCEN */
+ gpiod_set_value_cansleep(scen, 0);
+ /* Satisfies SCEN pulse width */
+ udelay(1);
+
+ return inval;
+}
+
+static u8 tpg110_read_reg(u8 address)
+{
+ return tpg110_readwrite_reg(false, address, 0);
+}
+
+static void tpg110_write_reg(u8 address, u8 outval)
+{
+ tpg110_readwrite_reg(true, address, outval);
+}
+
+static void tpg110_startup(struct device *dev)
+{
+ u8 val;
+
+ dev_info(dev, "TPG110 display enable\n");
+ /* De-assert the reset signal */
+ gpiod_set_value_cansleep(grestb, 0);
+ mdelay(1);
+ dev_info(dev, "de-asserted GRESTB\n");
+
+ /* Test display communication */
+ tpg110_write_reg(0x00, 0x55);
+ val = tpg110_read_reg(0x00);
+ if (val == 0x55)
+ dev_info(dev, "passed communication test\n");
+ val = tpg110_read_reg(0x01);
+ dev_info(dev, "TPG110 chip ID: %d version: %d\n",
+ val>>4, val&0x0f);
+
+ /* Show display resolution */
+ val = tpg110_read_reg(0x02);
+ val &= 7;
+ switch (val) {
+ case 0x0:
+ dev_info(dev, "IN 400x240 RGB -> OUT 800x480 RGB (dual scan)");
+ break;
+ case 0x1:
+ dev_info(dev, "IN 480x272 RGB -> OUT 800x480 RGB (dual scan)");
+ break;
+ case 0x4:
+ dev_info(dev, "480x640 RGB");
+ break;
+ case 0x5:
+ dev_info(dev, "480x272 RGB");
+ break;
+ case 0x6:
+ dev_info(dev, "640x480 RGB");
+ break;
+ case 0x7:
+ dev_info(dev, "800x480 RGB");
+ break;
+ default:
+ dev_info(dev, "ILLEGAL RESOLUTION");
+ break;
+ }
+
+ val = tpg110_read_reg(0x03);
+ dev_info(dev, "resolution is controlled by %s\n",
+ (val & BIT(7)) ? "software" : "hardware");
+}
+
+static void tpg110_enable(struct clcd_fb *fb)
+{
+ struct device *dev = &fb->dev->dev;
+ static bool startup;
+ u8 val;
+
+ if (!startup) {
+ tpg110_startup(dev);
+ startup = true;
+ }
+
+ /* Take chip out of standby */
+ val = tpg110_read_reg(0x03);
+ val |= BIT(0);
+ tpg110_write_reg(0x03, val);
+}
+
+static void tpg110_disable(struct clcd_fb *fb)
+{
+ u8 val;
+
+ dev_info(&fb->dev->dev, "TPG110 display disable\n");
+ val = tpg110_read_reg(0x03);
+ /* Put into standby */
+ val &= ~BIT(0);
+ tpg110_write_reg(0x03, val);
+}
+
+static void tpg110_init(struct device *dev, struct device_node *np,
+ struct clcd_board *board)
+{
+ dev_info(dev, "TPG110 display init\n");
+
+ grestb = devm_get_gpiod_from_child(dev, "grestb", &np->fwnode);
+ if (IS_ERR(grestb)) {
+ dev_err(dev, "no GRESTB GPIO\n");
+ return;
+ }
+ /* This asserts the GRESTB signal, putting the display into reset */
+ gpiod_direction_output(grestb, 1);
+
+ scen = devm_get_gpiod_from_child(dev, "scen", &np->fwnode);
+ if (IS_ERR(scen)) {
+ dev_err(dev, "no SCEN GPIO\n");
+ return;
+ }
+ gpiod_direction_output(scen, 0);
+ scl = devm_get_gpiod_from_child(dev, "scl", &np->fwnode);
+ if (IS_ERR(scl)) {
+ dev_err(dev, "no SCL GPIO\n");
+ return;
+ }
+ gpiod_direction_output(scl, 0);
+ sda = devm_get_gpiod_from_child(dev, "sda", &np->fwnode);
+ if (IS_ERR(sda)) {
+ dev_err(dev, "no SDA GPIO\n");
+ return;
+ }
+ gpiod_direction_output(sda, 0);
+ board->enable = tpg110_enable;
+ board->disable = tpg110_disable;
+}
+
+int nomadik_clcd_init_panel(struct clcd_fb *fb,
+ struct device_node *endpoint)
+{
+ struct device_node *panel;
+
+ panel = of_graph_get_remote_port_parent(endpoint);
+ if (!panel)
+ return -ENODEV;
+
+ if (of_device_is_compatible(panel, "tpo,tpg110"))
+ tpg110_init(&fb->dev->dev, panel, fb->board);
+ else
+ dev_info(&fb->dev->dev, "unknown panel\n");
+
+ /* Unknown panel, fall through */
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nomadik_clcd_init_panel);
+
+#define PMU_CTRL_OFFSET 0x0000
+#define PMU_CTRL_LCDNDIF BIT(26)
+
+int nomadik_clcd_init_board(struct amba_device *adev,
+ struct clcd_board *board)
+{
+ struct regmap *pmu_regmap;
+
+ dev_info(&adev->dev, "Nomadik CLCD board init\n");
+ pmu_regmap =
+ syscon_regmap_lookup_by_compatible("stericsson,nomadik-pmu");
+ if (IS_ERR(pmu_regmap)) {
+ dev_err(&adev->dev, "could not find PMU syscon regmap\n");
+ return PTR_ERR(pmu_regmap);
+ }
+ regmap_update_bits(pmu_regmap,
+ PMU_CTRL_OFFSET,
+ PMU_CTRL_LCDNDIF,
+ 0);
+ dev_info(&adev->dev, "set PMU mux to CLCD mode\n");
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(nomadik_clcd_init_board);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-29 05:58:27 +0100