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authormokopatches <mokopatches@openmoko.org>2008-11-19 17:03:10 +0000
committerwarmcat <andy@warmcat.com>2008-11-19 17:03:10 +0000
commit8b55ddd7b1655f0e674ff680910d3b50c812e207 (patch)
tree3da5ae1112348e7b56a701464f478f21a706d0ce
parente884b7a9eade8243363c736785a99d7c6e54d7df (diff)
gta01-jbt6k74.patch
This driver adds support for the SPI-based control interface of the LCM (LCD Panel) found on the FIC GTA01 hardware. The specific panel in this hardware is a TPO TD028TTEC1, but the driver should be able to drive any other diplay based on the JBT6K74-AS controller ASIC. Signed-off-by: Harald Welte <laforge@openmoko.org>
-rw-r--r--arch/arm/mach-s3c2410/Kconfig1
-rw-r--r--drivers/video/display/Kconfig11
-rw-r--r--drivers/video/display/Makefile1
-rw-r--r--drivers/video/display/jbt6k74.c678
4 files changed, 691 insertions, 0 deletions
diff --git a/arch/arm/mach-s3c2410/Kconfig b/arch/arm/mach-s3c2410/Kconfig
index 528e112f4d1..4c9c2e176d0 100644
--- a/arch/arm/mach-s3c2410/Kconfig
+++ b/arch/arm/mach-s3c2410/Kconfig
@@ -127,6 +127,7 @@ config MACH_VR1000
config MACH_QT2410
bool "QT2410"
select CPU_S3C2410
+ select DISPLAY_JBT6K74
help
Say Y here if you are using the Armzone QT2410
diff --git a/drivers/video/display/Kconfig b/drivers/video/display/Kconfig
index f99af931d4f..f0da4834e2d 100644
--- a/drivers/video/display/Kconfig
+++ b/drivers/video/display/Kconfig
@@ -21,4 +21,15 @@ config DISPLAY_SUPPORT
comment "Display hardware drivers"
depends on DISPLAY_SUPPORT
+config DISPLAY_JBT6K74
+ tristate "TPO JBT6K74-AS TFT display ASIC control interface"
+ depends on SPI_MASTER && SYSFS
+ help
+ SPI driver for the control interface of TFT panels containing
+ the TPO JBT6K74-AS controller ASIC, such as the TPO TD028TTEC1
+ TFT diplay module used in the FIC/OpenMoko Neo1973 GSM phones.
+
+ The control interface is required for display operation, as it
+ controls power management, display timing and gamma calibration.
+
endmenu
diff --git a/drivers/video/display/Makefile b/drivers/video/display/Makefile
index c0ea832bf17..011b69ddcea 100644
--- a/drivers/video/display/Makefile
+++ b/drivers/video/display/Makefile
@@ -3,4 +3,5 @@
display-objs := display-sysfs.o
obj-$(CONFIG_DISPLAY_SUPPORT) += display.o
+obj-$(CONFIG_DISPLAY_JBT6K74) += jbt6k74.o
diff --git a/drivers/video/display/jbt6k74.c b/drivers/video/display/jbt6k74.c
new file mode 100644
index 00000000000..d021d7e34c0
--- /dev/null
+++ b/drivers/video/display/jbt6k74.c
@@ -0,0 +1,678 @@
+/* Linux kernel driver for the tpo JBT6K74-AS LCM ASIC
+ *
+ * Copyright (C) 2006-2007 by OpenMoko, Inc.
+ * Author: Harald Welte <laforge@openmoko.org>,
+ * Stefan Schmidt <stefan@openmoko.org>
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ *
+ */
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+
+#include <linux/spi/spi.h>
+
+enum jbt_register {
+ JBT_REG_SLEEP_IN = 0x10,
+ JBT_REG_SLEEP_OUT = 0x11,
+
+ JBT_REG_DISPLAY_OFF = 0x28,
+ JBT_REG_DISPLAY_ON = 0x29,
+
+ JBT_REG_RGB_FORMAT = 0x3a,
+ JBT_REG_QUAD_RATE = 0x3b,
+
+ JBT_REG_POWER_ON_OFF = 0xb0,
+ JBT_REG_BOOSTER_OP = 0xb1,
+ JBT_REG_BOOSTER_MODE = 0xb2,
+ JBT_REG_BOOSTER_FREQ = 0xb3,
+ JBT_REG_OPAMP_SYSCLK = 0xb4,
+ JBT_REG_VSC_VOLTAGE = 0xb5,
+ JBT_REG_VCOM_VOLTAGE = 0xb6,
+ JBT_REG_EXT_DISPL = 0xb7,
+ JBT_REG_OUTPUT_CONTROL = 0xb8,
+ JBT_REG_DCCLK_DCEV = 0xb9,
+ JBT_REG_DISPLAY_MODE1 = 0xba,
+ JBT_REG_DISPLAY_MODE2 = 0xbb,
+ JBT_REG_DISPLAY_MODE = 0xbc,
+ JBT_REG_ASW_SLEW = 0xbd,
+ JBT_REG_DUMMY_DISPLAY = 0xbe,
+ JBT_REG_DRIVE_SYSTEM = 0xbf,
+
+ JBT_REG_SLEEP_OUT_FR_A = 0xc0,
+ JBT_REG_SLEEP_OUT_FR_B = 0xc1,
+ JBT_REG_SLEEP_OUT_FR_C = 0xc2,
+ JBT_REG_SLEEP_IN_LCCNT_D = 0xc3,
+ JBT_REG_SLEEP_IN_LCCNT_E = 0xc4,
+ JBT_REG_SLEEP_IN_LCCNT_F = 0xc5,
+ JBT_REG_SLEEP_IN_LCCNT_G = 0xc6,
+
+ JBT_REG_GAMMA1_FINE_1 = 0xc7,
+ JBT_REG_GAMMA1_FINE_2 = 0xc8,
+ JBT_REG_GAMMA1_INCLINATION = 0xc9,
+ JBT_REG_GAMMA1_BLUE_OFFSET = 0xca,
+
+ /* VGA */
+ JBT_REG_BLANK_CONTROL = 0xcf,
+ JBT_REG_BLANK_TH_TV = 0xd0,
+ JBT_REG_CKV_ON_OFF = 0xd1,
+ JBT_REG_CKV_1_2 = 0xd2,
+ JBT_REG_OEV_TIMING = 0xd3,
+ JBT_REG_ASW_TIMING_1 = 0xd4,
+ JBT_REG_ASW_TIMING_2 = 0xd5,
+
+ /* QVGA */
+ JBT_REG_BLANK_CONTROL_QVGA = 0xd6,
+ JBT_REG_BLANK_TH_TV_QVGA = 0xd7,
+ JBT_REG_CKV_ON_OFF_QVGA = 0xd8,
+ JBT_REG_CKV_1_2_QVGA = 0xd9,
+ JBT_REG_OEV_TIMING_QVGA = 0xde,
+ JBT_REG_ASW_TIMING_1_QVGA = 0xdf,
+ JBT_REG_ASW_TIMING_2_QVGA = 0xe0,
+
+
+ JBT_REG_HCLOCK_VGA = 0xec,
+ JBT_REG_HCLOCK_QVGA = 0xed,
+
+};
+
+enum jbt_state {
+ JBT_STATE_DEEP_STANDBY,
+ JBT_STATE_SLEEP,
+ JBT_STATE_NORMAL,
+ JBT_STATE_QVGA_NORMAL,
+};
+
+static const char *jbt_state_names[] = {
+ [JBT_STATE_DEEP_STANDBY] = "deep-standby",
+ [JBT_STATE_SLEEP] = "sleep",
+ [JBT_STATE_NORMAL] = "normal",
+ [JBT_STATE_QVGA_NORMAL] = "qvga-normal",
+};
+
+struct jbt_info {
+ enum jbt_state state, last_state;
+ struct spi_device *spi_dev;
+ struct mutex lock; /* protects tx_buf and reg_cache */
+ u16 tx_buf[8];
+ u16 reg_cache[0xEE];
+};
+
+#define JBT_COMMAND 0x000
+#define JBT_DATA 0x100
+
+static int jbt_reg_write_nodata(struct jbt_info *jbt, u8 reg)
+{
+ int rc;
+
+ mutex_lock(&jbt->lock);
+
+ jbt->tx_buf[0] = JBT_COMMAND | reg;
+ rc = spi_write(jbt->spi_dev, (u8 *)jbt->tx_buf,
+ 1*sizeof(u16));
+ if (rc == 0)
+ jbt->reg_cache[reg] = 0;
+
+ mutex_unlock(&jbt->lock);
+
+ return rc;
+}
+
+
+static int jbt_reg_write(struct jbt_info *jbt, u8 reg, u8 data)
+{
+ int rc;
+
+ mutex_lock(&jbt->lock);
+
+ jbt->tx_buf[0] = JBT_COMMAND | reg;
+ jbt->tx_buf[1] = JBT_DATA | data;
+ rc = spi_write(jbt->spi_dev, (u8 *)jbt->tx_buf,
+ 2*sizeof(u16));
+ if (rc == 0)
+ jbt->reg_cache[reg] = data;
+
+ mutex_unlock(&jbt->lock);
+
+ return rc;
+}
+
+static int jbt_reg_write16(struct jbt_info *jbt, u8 reg, u16 data)
+{
+ int rc;
+
+ mutex_lock(&jbt->lock);
+
+ jbt->tx_buf[0] = JBT_COMMAND | reg;
+ jbt->tx_buf[1] = JBT_DATA | (data >> 8);
+ jbt->tx_buf[2] = JBT_DATA | (data & 0xff);
+
+ rc = spi_write(jbt->spi_dev, (u8 *)jbt->tx_buf,
+ 3*sizeof(u16));
+ if (rc == 0)
+ jbt->reg_cache[reg] = data;
+
+ mutex_unlock(&jbt->lock);
+
+ return rc;
+}
+
+static int jbt_init_regs(struct jbt_info *jbt, int qvga)
+{
+ int rc;
+
+ dev_dbg(&jbt->spi_dev->dev, "entering %cVGA mode\n", qvga ? 'Q' : ' ');
+
+ rc = jbt_reg_write(jbt, JBT_REG_DISPLAY_MODE1, 0x01);
+ rc |= jbt_reg_write(jbt, JBT_REG_DISPLAY_MODE2, 0x00);
+ rc |= jbt_reg_write(jbt, JBT_REG_RGB_FORMAT, 0x60);
+ rc |= jbt_reg_write(jbt, JBT_REG_DRIVE_SYSTEM, 0x10);
+ rc |= jbt_reg_write(jbt, JBT_REG_BOOSTER_OP, 0x56);
+ rc |= jbt_reg_write(jbt, JBT_REG_BOOSTER_MODE, 0x33);
+ rc |= jbt_reg_write(jbt, JBT_REG_BOOSTER_FREQ, 0x11);
+ rc |= jbt_reg_write(jbt, JBT_REG_OPAMP_SYSCLK, 0x02);
+ rc |= jbt_reg_write(jbt, JBT_REG_VSC_VOLTAGE, 0x2b);
+ rc |= jbt_reg_write(jbt, JBT_REG_VCOM_VOLTAGE, 0x40);
+ rc |= jbt_reg_write(jbt, JBT_REG_EXT_DISPL, 0x03);
+ rc |= jbt_reg_write(jbt, JBT_REG_DCCLK_DCEV, 0x04);
+ /*
+ * default of 0x02 in JBT_REG_ASW_SLEW responsible for 72Hz requirement
+ * to avoid red / blue flicker
+ */
+ rc |= jbt_reg_write(jbt, JBT_REG_ASW_SLEW, 0x04);
+ rc |= jbt_reg_write(jbt, JBT_REG_DUMMY_DISPLAY, 0x00);
+
+ rc |= jbt_reg_write(jbt, JBT_REG_SLEEP_OUT_FR_A, 0x11);
+ rc |= jbt_reg_write(jbt, JBT_REG_SLEEP_OUT_FR_B, 0x11);
+ rc |= jbt_reg_write(jbt, JBT_REG_SLEEP_OUT_FR_C, 0x11);
+ rc |= jbt_reg_write16(jbt, JBT_REG_SLEEP_IN_LCCNT_D, 0x2040);
+ rc |= jbt_reg_write16(jbt, JBT_REG_SLEEP_IN_LCCNT_E, 0x60c0);
+ rc |= jbt_reg_write16(jbt, JBT_REG_SLEEP_IN_LCCNT_F, 0x1020);
+ rc |= jbt_reg_write16(jbt, JBT_REG_SLEEP_IN_LCCNT_G, 0x60c0);
+
+ rc |= jbt_reg_write16(jbt, JBT_REG_GAMMA1_FINE_1, 0x5533);
+ rc |= jbt_reg_write(jbt, JBT_REG_GAMMA1_FINE_2, 0x00);
+ rc |= jbt_reg_write(jbt, JBT_REG_GAMMA1_INCLINATION, 0x00);
+ rc |= jbt_reg_write(jbt, JBT_REG_GAMMA1_BLUE_OFFSET, 0x00);
+
+ if (!qvga) {
+ rc |= jbt_reg_write16(jbt, JBT_REG_HCLOCK_VGA, 0x1f0);
+ rc |= jbt_reg_write(jbt, JBT_REG_BLANK_CONTROL, 0x02);
+ rc |= jbt_reg_write16(jbt, JBT_REG_BLANK_TH_TV, 0x0804);
+
+ rc |= jbt_reg_write(jbt, JBT_REG_CKV_ON_OFF, 0x01);
+ rc |= jbt_reg_write16(jbt, JBT_REG_CKV_1_2, 0x0000);
+
+ rc |= jbt_reg_write16(jbt, JBT_REG_OEV_TIMING, 0x0d0e);
+ rc |= jbt_reg_write16(jbt, JBT_REG_ASW_TIMING_1, 0x11a4);
+ rc |= jbt_reg_write(jbt, JBT_REG_ASW_TIMING_2, 0x0e);
+ } else {
+ rc |= jbt_reg_write16(jbt, JBT_REG_HCLOCK_QVGA, 0x00ff);
+ rc |= jbt_reg_write(jbt, JBT_REG_BLANK_CONTROL_QVGA, 0x02);
+ rc |= jbt_reg_write16(jbt, JBT_REG_BLANK_TH_TV_QVGA, 0x0804);
+
+ rc |= jbt_reg_write(jbt, JBT_REG_CKV_ON_OFF_QVGA, 0x01);
+ rc |= jbt_reg_write16(jbt, JBT_REG_CKV_1_2_QVGA, 0x0008);
+
+ rc |= jbt_reg_write16(jbt, JBT_REG_OEV_TIMING_QVGA, 0x050a);
+ rc |= jbt_reg_write16(jbt, JBT_REG_ASW_TIMING_1_QVGA, 0x0a19);
+ rc |= jbt_reg_write(jbt, JBT_REG_ASW_TIMING_2_QVGA, 0x0a);
+ }
+
+ return rc ? -EIO : 0;
+}
+
+static int standby_to_sleep(struct jbt_info *jbt)
+{
+ int rc;
+
+ /* three times command zero */
+ rc = jbt_reg_write_nodata(jbt, 0x00);
+ mdelay(1);
+ rc |= jbt_reg_write_nodata(jbt, 0x00);
+ mdelay(1);
+ rc |= jbt_reg_write_nodata(jbt, 0x00);
+ mdelay(1);
+
+ /* deep standby out */
+ rc |= jbt_reg_write(jbt, JBT_REG_POWER_ON_OFF, 0x17);
+
+ return rc ? -EIO : 0;
+}
+
+static int sleep_to_normal(struct jbt_info *jbt)
+{
+ int rc;
+
+ /* RGB I/F on, RAM wirte off, QVGA through, SIGCON enable */
+ rc = jbt_reg_write(jbt, JBT_REG_DISPLAY_MODE, 0x80);
+
+ /* Quad mode off */
+ rc |= jbt_reg_write(jbt, JBT_REG_QUAD_RATE, 0x00);
+
+ /* AVDD on, XVDD on */
+ rc |= jbt_reg_write(jbt, JBT_REG_POWER_ON_OFF, 0x16);
+
+ /* Output control */
+ rc |= jbt_reg_write16(jbt, JBT_REG_OUTPUT_CONTROL, 0xfff9);
+
+ /* Sleep mode off */
+ rc |= jbt_reg_write_nodata(jbt, JBT_REG_SLEEP_OUT);
+
+ /* initialize register set */
+ rc |= jbt_init_regs(jbt, 0);
+
+ return rc ? -EIO : 0;
+}
+
+static int sleep_to_qvga_normal(struct jbt_info *jbt)
+{
+ int rc;
+
+ /* RGB I/F on, RAM wirte off, QVGA through, SIGCON enable */
+ rc = jbt_reg_write(jbt, JBT_REG_DISPLAY_MODE, 0x81);
+
+ /* Quad mode on */
+ rc |= jbt_reg_write(jbt, JBT_REG_QUAD_RATE, 0x22);
+
+ /* AVDD on, XVDD on */
+ rc |= jbt_reg_write(jbt, JBT_REG_POWER_ON_OFF, 0x16);
+
+ /* Output control */
+ rc |= jbt_reg_write16(jbt, JBT_REG_OUTPUT_CONTROL, 0xfff9);
+
+ /* Sleep mode off */
+ rc |= jbt_reg_write_nodata(jbt, JBT_REG_SLEEP_OUT);
+
+ /* initialize register set for qvga*/
+ rc |= jbt_init_regs(jbt, 1);
+
+ return rc ? -EIO : 0;
+}
+
+static int normal_to_sleep(struct jbt_info *jbt)
+{
+ int rc;
+
+ rc = jbt_reg_write_nodata(jbt, JBT_REG_DISPLAY_OFF);
+ rc |= jbt_reg_write16(jbt, JBT_REG_OUTPUT_CONTROL, 0x8002);
+ rc |= jbt_reg_write_nodata(jbt, JBT_REG_SLEEP_IN);
+
+ return rc ? -EIO : 0;
+}
+
+static int sleep_to_standby(struct jbt_info *jbt)
+{
+ return jbt_reg_write(jbt, JBT_REG_POWER_ON_OFF, 0x00);
+}
+
+/* frontend function */
+int jbt6k74_enter_state(struct jbt_info *jbt, enum jbt_state new_state)
+{
+ int rc = -EINVAL;
+
+ dev_dbg(&jbt->spi_dev->dev, "entering (old_state=%u, "
+ "new_state=%u)\n", jbt->state, new_state);
+
+ switch (jbt->state) {
+ case JBT_STATE_DEEP_STANDBY:
+ switch (new_state) {
+ case JBT_STATE_DEEP_STANDBY:
+ rc = 0;
+ break;
+ case JBT_STATE_SLEEP:
+ rc = standby_to_sleep(jbt);
+ break;
+ case JBT_STATE_NORMAL:
+ /* first transition into sleep */
+ rc = standby_to_sleep(jbt);
+ /* then transition into normal */
+ rc |= sleep_to_normal(jbt);
+ break;
+ case JBT_STATE_QVGA_NORMAL:
+ /* first transition into sleep */
+ rc = standby_to_sleep(jbt);
+ /* then transition into normal */
+ rc |= sleep_to_qvga_normal(jbt);
+ break;
+ }
+ break;
+ case JBT_STATE_SLEEP:
+ switch (new_state) {
+ case JBT_STATE_SLEEP:
+ rc = 0;
+ break;
+ case JBT_STATE_DEEP_STANDBY:
+ rc = sleep_to_standby(jbt);
+ break;
+ case JBT_STATE_NORMAL:
+ rc = sleep_to_normal(jbt);
+ break;
+ case JBT_STATE_QVGA_NORMAL:
+ rc = sleep_to_qvga_normal(jbt);
+ break;
+ }
+ break;
+ case JBT_STATE_NORMAL:
+ switch (new_state) {
+ case JBT_STATE_NORMAL:
+ rc = 0;
+ break;
+ case JBT_STATE_DEEP_STANDBY:
+ /* first transition into sleep */
+ rc = normal_to_sleep(jbt);
+ /* then transition into deep standby */
+ rc |= sleep_to_standby(jbt);
+ break;
+ case JBT_STATE_SLEEP:
+ rc = normal_to_sleep(jbt);
+ break;
+ case JBT_STATE_QVGA_NORMAL:
+ /* first transition into sleep */
+ rc = normal_to_sleep(jbt);
+ /* second transition into deep standby */
+ rc |= sleep_to_standby(jbt);
+ /* third transition into sleep */
+ rc |= standby_to_sleep(jbt);
+ /* fourth transition into normal */
+ rc |= sleep_to_qvga_normal(jbt);
+ break;
+ }
+ break;
+ case JBT_STATE_QVGA_NORMAL:
+ switch (new_state) {
+ case JBT_STATE_QVGA_NORMAL:
+ rc = 0;
+ break;
+ case JBT_STATE_DEEP_STANDBY:
+ /* first transition into sleep */
+ rc = normal_to_sleep(jbt);
+ /* then transition into deep standby */
+ rc |= sleep_to_standby(jbt);
+ break;
+ case JBT_STATE_SLEEP:
+ rc = normal_to_sleep(jbt);
+ break;
+ case JBT_STATE_NORMAL:
+ /* first transition into sleep */
+ rc = normal_to_sleep(jbt);
+ /* second transition into deep standby */
+ rc |= sleep_to_standby(jbt);
+ /* third transition into sleep */
+ rc |= standby_to_sleep(jbt);
+ /* fourth transition into normal */
+ rc |= sleep_to_normal(jbt);
+ break;
+ }
+ break;
+ }
+ if (rc == 0)
+ jbt->state = new_state;
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(jbt6k74_enter_state);
+
+int jbt6k74_display_onoff(struct jbt_info *jbt, int on)
+{
+ if (on)
+ return jbt_reg_write_nodata(jbt, JBT_REG_DISPLAY_ON);
+ else
+ return jbt_reg_write_nodata(jbt, JBT_REG_DISPLAY_OFF);
+}
+EXPORT_SYMBOL_GPL(jbt6k74_display_onoff);
+
+static ssize_t state_read(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct jbt_info *jbt = dev_get_drvdata(dev);
+
+ if (jbt->state >= ARRAY_SIZE(jbt_state_names))
+ return -EIO;
+
+ return sprintf(buf, "%s\n", jbt_state_names[jbt->state]);
+}
+
+static ssize_t state_write(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct jbt_info *jbt = dev_get_drvdata(dev);
+ int i, rc;
+
+ for (i = 0; i < ARRAY_SIZE(jbt_state_names); i++) {
+ if (!strncmp(buf, jbt_state_names[i],
+ strlen(jbt_state_names[i]))) {
+ rc = jbt6k74_enter_state(jbt, i);
+ if (rc)
+ return rc;
+ switch (i) {
+ case JBT_STATE_NORMAL:
+ case JBT_STATE_QVGA_NORMAL:
+ /* Enable display again after deep-standby */
+ rc = jbt6k74_display_onoff(jbt, 1);
+ if (rc)
+ return rc;
+ break;
+ default:
+ break;
+ }
+ return count;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static DEVICE_ATTR(state, 0644, state_read, state_write);
+
+static int reg_by_string(const char *name)
+{
+ if (!strcmp(name, "gamma_fine1"))
+ return JBT_REG_GAMMA1_FINE_1;
+ else if (!strcmp(name, "gamma_fine2"))
+ return JBT_REG_GAMMA1_FINE_2;
+ else if (!strcmp(name, "gamma_inclination"))
+ return JBT_REG_GAMMA1_INCLINATION;
+ else
+ return JBT_REG_GAMMA1_BLUE_OFFSET;
+}
+
+static ssize_t gamma_read(struct device *dev, struct device_attribute *attr,
+ char *buf)
+{
+ struct jbt_info *jbt = dev_get_drvdata(dev);
+ int reg = reg_by_string(attr->attr.name);
+ u16 val;
+
+ mutex_lock(&jbt->lock);
+ val = jbt->reg_cache[reg];
+ mutex_unlock(&jbt->lock);
+
+ return sprintf(buf, "0x%04x\n", val);
+}
+
+static ssize_t gamma_write(struct device *dev, struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct jbt_info *jbt = dev_get_drvdata(dev);
+ int reg = reg_by_string(attr->attr.name);
+ unsigned long val = simple_strtoul(buf, NULL, 10);
+
+ jbt_reg_write(jbt, reg, val & 0xff);
+
+ return count;
+}
+
+static DEVICE_ATTR(gamma_fine1, 0644, gamma_read, gamma_write);
+static DEVICE_ATTR(gamma_fine2, 0644, gamma_read, gamma_write);
+static DEVICE_ATTR(gamma_inclination, 0644, gamma_read, gamma_write);
+static DEVICE_ATTR(gamma_blue_offset, 0644, gamma_read, gamma_write);
+
+static struct attribute *jbt_sysfs_entries[] = {
+ &dev_attr_state.attr,
+ &dev_attr_gamma_fine1.attr,
+ &dev_attr_gamma_fine2.attr,
+ &dev_attr_gamma_inclination.attr,
+ &dev_attr_gamma_blue_offset.attr,
+ NULL,
+};
+
+static struct attribute_group jbt_attr_group = {
+ .name = NULL,
+ .attrs = jbt_sysfs_entries,
+};
+
+/* linux device model infrastructure */
+
+static int __devinit jbt_probe(struct spi_device *spi)
+{
+ int rc;
+ struct jbt_info *jbt;
+
+ /* the controller doesn't have a MISO pin; we can't do detection */
+
+ spi->mode = SPI_CPOL | SPI_CPHA;
+ spi->bits_per_word = 9;
+
+ rc = spi_setup(spi);
+ if (rc < 0) {
+ dev_err(&spi->dev,
+ "error during spi_setup of jbt6k74 driver\n");
+ return rc;
+ }
+
+ jbt = kzalloc(sizeof(*jbt), GFP_KERNEL);
+ if (!jbt)
+ return -ENOMEM;
+
+ jbt->spi_dev = spi;
+ jbt->state = JBT_STATE_DEEP_STANDBY;
+ mutex_init(&jbt->lock);
+
+ dev_set_drvdata(&spi->dev, jbt);
+
+ rc = jbt6k74_enter_state(jbt, JBT_STATE_NORMAL);
+ if (rc < 0) {
+ dev_err(&spi->dev, "cannot enter NORMAL state\n");
+ goto err_free_drvdata;
+ }
+
+ rc = jbt6k74_display_onoff(jbt, 1);
+ if (rc < 0) {
+ dev_err(&spi->dev, "cannot switch display on\n");
+ goto err_standby;
+ }
+
+ rc = sysfs_create_group(&spi->dev.kobj, &jbt_attr_group);
+ if (rc < 0) {
+ dev_err(&spi->dev, "cannot create sysfs group\n");
+ goto err_off;
+ }
+
+ return 0;
+
+err_off:
+ jbt6k74_display_onoff(jbt, 0);
+err_standby:
+ jbt6k74_enter_state(jbt, JBT_STATE_DEEP_STANDBY);
+err_free_drvdata:
+ dev_set_drvdata(&spi->dev, NULL);
+ kfree(jbt);
+
+ return rc;
+}
+
+static int __devexit jbt_remove(struct spi_device *spi)
+{
+ struct jbt_info *jbt = dev_get_drvdata(&spi->dev);
+
+ /* We don't want to switch off the display in case the user
+ * accidentially onloads the module (whose use count normally is 0) */
+
+ sysfs_remove_group(&spi->dev.kobj, &jbt_attr_group);
+ dev_set_drvdata(&spi->dev, NULL);
+ kfree(jbt);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int jbt_suspend(struct spi_device *spi, pm_message_t state)
+{
+ struct jbt_info *jbt = dev_get_drvdata(&spi->dev);
+
+ /* Save mode for resume */
+ jbt->last_state = jbt->state;
+ jbt6k74_enter_state(jbt, JBT_STATE_DEEP_STANDBY);
+
+ return 0;
+}
+
+static int jbt_resume(struct spi_device *spi)
+{
+ struct jbt_info *jbt = dev_get_drvdata(&spi->dev);
+
+ jbt6k74_enter_state(jbt, jbt->last_state);
+
+ switch (jbt->last_state) {
+ case JBT_STATE_NORMAL:
+ case JBT_STATE_QVGA_NORMAL:
+ jbt6k74_display_onoff(jbt, 1);
+ break;
+ default:
+ break;
+ }
+
+ return 0;
+}
+#else
+#define jbt_suspend NULL
+#define jbt_resume NULL
+#endif
+
+static struct spi_driver jbt6k74_driver = {
+ .driver = {
+ .name = "jbt6k74",
+ .owner = THIS_MODULE,
+ },
+
+ .probe = jbt_probe,
+ .remove = __devexit_p(jbt_remove),
+ .suspend = jbt_suspend,
+ .resume = jbt_resume,
+};
+
+static int __init jbt_init(void)
+{
+ return spi_register_driver(&jbt6k74_driver);
+}
+
+static void __exit jbt_exit(void)
+{
+ spi_unregister_driver(&jbt6k74_driver);
+}
+
+MODULE_DESCRIPTION("SPI driver for tpo JBT6K74-AS LCM control interface");
+MODULE_AUTHOR("Harald Welte <laforge@openmoko.org>");
+MODULE_LICENSE("GPL");
+
+module_init(jbt_init);
+module_exit(jbt_exit);