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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /drivers/video/backlight/ltv350qv.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'drivers/video/backlight/ltv350qv.c')
-rw-r--r--drivers/video/backlight/ltv350qv.c305
1 files changed, 305 insertions, 0 deletions
diff --git a/drivers/video/backlight/ltv350qv.c b/drivers/video/backlight/ltv350qv.c
new file mode 100644
index 000000000..c919b0fe4
--- /dev/null
+++ b/drivers/video/backlight/ltv350qv.c
@@ -0,0 +1,305 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Power control for Samsung LTV350QV Quarter VGA LCD Panel
+ *
+ * Copyright (C) 2006, 2007 Atmel Corporation
+ */
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/lcd.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+
+#include "ltv350qv.h"
+
+#define POWER_IS_ON(pwr) ((pwr) <= LCD_POWER_REDUCED)
+
+struct ltv350qv {
+ struct spi_device *spi;
+ u8 *buffer;
+ int power;
+ struct lcd_device *ld;
+};
+
+/*
+ * The power-on and power-off sequences are taken from the
+ * LTV350QV-F04 data sheet from Samsung. The register definitions are
+ * taken from the S6F2002 command list also from Samsung.
+ *
+ * There's still some voodoo going on here, but it's a lot better than
+ * in the first incarnation of the driver where all we had was the raw
+ * numbers from the initialization sequence.
+ */
+static int ltv350qv_write_reg(struct ltv350qv *lcd, u8 reg, u16 val)
+{
+ struct spi_message msg;
+ struct spi_transfer index_xfer = {
+ .len = 3,
+ .cs_change = 1,
+ };
+ struct spi_transfer value_xfer = {
+ .len = 3,
+ };
+
+ spi_message_init(&msg);
+
+ /* register index */
+ lcd->buffer[0] = LTV_OPC_INDEX;
+ lcd->buffer[1] = 0x00;
+ lcd->buffer[2] = reg & 0x7f;
+ index_xfer.tx_buf = lcd->buffer;
+ spi_message_add_tail(&index_xfer, &msg);
+
+ /* register value */
+ lcd->buffer[4] = LTV_OPC_DATA;
+ lcd->buffer[5] = val >> 8;
+ lcd->buffer[6] = val;
+ value_xfer.tx_buf = lcd->buffer + 4;
+ spi_message_add_tail(&value_xfer, &msg);
+
+ return spi_sync(lcd->spi, &msg);
+}
+
+/* The comments are taken straight from the data sheet */
+static int ltv350qv_power_on(struct ltv350qv *lcd)
+{
+ int ret;
+
+ /* Power On Reset Display off State */
+ if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, 0x0000))
+ goto err;
+ usleep_range(15000, 16000);
+
+ /* Power Setting Function 1 */
+ if (ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE))
+ goto err;
+ if (ltv350qv_write_reg(lcd, LTV_PWRCTL2, LTV_VCOML_ENABLE))
+ goto err_power1;
+
+ /* Power Setting Function 2 */
+ if (ltv350qv_write_reg(lcd, LTV_PWRCTL1,
+ LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5)
+ | LTV_SUPPLY_CURRENT(5)))
+ goto err_power2;
+
+ msleep(55);
+
+ /* Instruction Setting */
+ ret = ltv350qv_write_reg(lcd, LTV_IFCTL,
+ LTV_NMD | LTV_REV | LTV_NL(0x1d));
+ ret |= ltv350qv_write_reg(lcd, LTV_DATACTL,
+ LTV_DS_SAME | LTV_CHS_480
+ | LTV_DF_RGB | LTV_RGB_BGR);
+ ret |= ltv350qv_write_reg(lcd, LTV_ENTRY_MODE,
+ LTV_VSPL_ACTIVE_LOW
+ | LTV_HSPL_ACTIVE_LOW
+ | LTV_DPL_SAMPLE_RISING
+ | LTV_EPL_ACTIVE_LOW
+ | LTV_SS_RIGHT_TO_LEFT);
+ ret |= ltv350qv_write_reg(lcd, LTV_GATECTL1, LTV_CLW(3));
+ ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2,
+ LTV_NW_INV_1LINE | LTV_FWI(3));
+ ret |= ltv350qv_write_reg(lcd, LTV_VBP, 0x000a);
+ ret |= ltv350qv_write_reg(lcd, LTV_HBP, 0x0021);
+ ret |= ltv350qv_write_reg(lcd, LTV_SOTCTL, LTV_SDT(3) | LTV_EQ(0));
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(0), 0x0103);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(1), 0x0301);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(2), 0x1f0f);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(3), 0x1f0f);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(4), 0x0707);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(5), 0x0307);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(6), 0x0707);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(7), 0x0000);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(8), 0x0004);
+ ret |= ltv350qv_write_reg(lcd, LTV_GAMMA(9), 0x0000);
+ if (ret)
+ goto err_settings;
+
+ /* Wait more than 2 frames */
+ msleep(20);
+
+ /* Display On Sequence */
+ ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1,
+ LTV_VCOM_DISABLE | LTV_VCOMOUT_ENABLE
+ | LTV_POWER_ON | LTV_DRIVE_CURRENT(5)
+ | LTV_SUPPLY_CURRENT(5));
+ ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2,
+ LTV_NW_INV_1LINE | LTV_DSC | LTV_FWI(3));
+ if (ret)
+ goto err_disp_on;
+
+ /* Display should now be ON. Phew. */
+ return 0;
+
+err_disp_on:
+ /*
+ * Try to recover. Error handling probably isn't very useful
+ * at this point, just make a best effort to switch the panel
+ * off.
+ */
+ ltv350qv_write_reg(lcd, LTV_PWRCTL1,
+ LTV_VCOM_DISABLE | LTV_DRIVE_CURRENT(5)
+ | LTV_SUPPLY_CURRENT(5));
+ ltv350qv_write_reg(lcd, LTV_GATECTL2,
+ LTV_NW_INV_1LINE | LTV_FWI(3));
+err_settings:
+err_power2:
+err_power1:
+ ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000);
+ usleep_range(1000, 1100);
+err:
+ ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE);
+ return -EIO;
+}
+
+static int ltv350qv_power_off(struct ltv350qv *lcd)
+{
+ int ret;
+
+ /* Display Off Sequence */
+ ret = ltv350qv_write_reg(lcd, LTV_PWRCTL1,
+ LTV_VCOM_DISABLE
+ | LTV_DRIVE_CURRENT(5)
+ | LTV_SUPPLY_CURRENT(5));
+ ret |= ltv350qv_write_reg(lcd, LTV_GATECTL2,
+ LTV_NW_INV_1LINE | LTV_FWI(3));
+
+ /* Power down setting 1 */
+ ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL2, 0x0000);
+
+ /* Wait at least 1 ms */
+ usleep_range(1000, 1100);
+
+ /* Power down setting 2 */
+ ret |= ltv350qv_write_reg(lcd, LTV_PWRCTL1, LTV_VCOM_DISABLE);
+
+ /*
+ * No point in trying to recover here. If we can't switch the
+ * panel off, what are we supposed to do other than inform the
+ * user about the failure?
+ */
+ if (ret)
+ return -EIO;
+
+ /* Display power should now be OFF */
+ return 0;
+}
+
+static int ltv350qv_power(struct ltv350qv *lcd, int power)
+{
+ int ret = 0;
+
+ if (POWER_IS_ON(power) && !POWER_IS_ON(lcd->power))
+ ret = ltv350qv_power_on(lcd);
+ else if (!POWER_IS_ON(power) && POWER_IS_ON(lcd->power))
+ ret = ltv350qv_power_off(lcd);
+
+ if (!ret)
+ lcd->power = power;
+
+ return ret;
+}
+
+static int ltv350qv_set_power(struct lcd_device *ld, int power)
+{
+ struct ltv350qv *lcd = lcd_get_data(ld);
+
+ return ltv350qv_power(lcd, power);
+}
+
+static int ltv350qv_get_power(struct lcd_device *ld)
+{
+ struct ltv350qv *lcd = lcd_get_data(ld);
+
+ return lcd->power;
+}
+
+static const struct lcd_ops ltv_ops = {
+ .get_power = ltv350qv_get_power,
+ .set_power = ltv350qv_set_power,
+};
+
+static int ltv350qv_probe(struct spi_device *spi)
+{
+ struct ltv350qv *lcd;
+ struct lcd_device *ld;
+ int ret;
+
+ lcd = devm_kzalloc(&spi->dev, sizeof(struct ltv350qv), GFP_KERNEL);
+ if (!lcd)
+ return -ENOMEM;
+
+ lcd->spi = spi;
+ lcd->power = LCD_POWER_OFF;
+ lcd->buffer = devm_kzalloc(&spi->dev, 8, GFP_KERNEL);
+ if (!lcd->buffer)
+ return -ENOMEM;
+
+ ld = devm_lcd_device_register(&spi->dev, "ltv350qv", &spi->dev, lcd,
+ &ltv_ops);
+ if (IS_ERR(ld))
+ return PTR_ERR(ld);
+
+ lcd->ld = ld;
+
+ ret = ltv350qv_power(lcd, LCD_POWER_ON);
+ if (ret)
+ return ret;
+
+ spi_set_drvdata(spi, lcd);
+
+ return 0;
+}
+
+static void ltv350qv_remove(struct spi_device *spi)
+{
+ struct ltv350qv *lcd = spi_get_drvdata(spi);
+
+ ltv350qv_power(lcd, LCD_POWER_OFF);
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int ltv350qv_suspend(struct device *dev)
+{
+ struct ltv350qv *lcd = dev_get_drvdata(dev);
+
+ return ltv350qv_power(lcd, LCD_POWER_OFF);
+}
+
+static int ltv350qv_resume(struct device *dev)
+{
+ struct ltv350qv *lcd = dev_get_drvdata(dev);
+
+ return ltv350qv_power(lcd, LCD_POWER_ON);
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(ltv350qv_pm_ops, ltv350qv_suspend, ltv350qv_resume);
+
+/* Power down all displays on reboot, poweroff or halt */
+static void ltv350qv_shutdown(struct spi_device *spi)
+{
+ struct ltv350qv *lcd = spi_get_drvdata(spi);
+
+ ltv350qv_power(lcd, LCD_POWER_OFF);
+}
+
+static struct spi_driver ltv350qv_driver = {
+ .driver = {
+ .name = "ltv350qv",
+ .pm = &ltv350qv_pm_ops,
+ },
+
+ .probe = ltv350qv_probe,
+ .remove = ltv350qv_remove,
+ .shutdown = ltv350qv_shutdown,
+};
+
+module_spi_driver(ltv350qv_driver);
+
+MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
+MODULE_DESCRIPTION("Samsung LTV350QV LCD Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:ltv350qv");