Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted

Pull I3C updates from Alexandre Belloni:
 "A new driver this cycle, for the AMD AXI I3C controller.

  There are also new features such as IBI wakeup support, SETAASA device
  discovery and ACPI support for the the DAA methods, meaning we can now
  communicate with the SPD devices on DDR5 modules.

  New driver:
   - AMD AXI I3C master controller

  Subsystem:
   - I3C Common Command Code (CCC) handling improvements, especially
     around GET CCCs
   - SETAASA device discovery support
   - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
     well as I2C devices on I3C bus
   - IBI-based wakeup support

  Drivers:
   - dw: SETAASA support
   - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
     controller support, PIO queue management support for HCI v1.2
   - renesas: improve suspend to RAM support, add runtime PM support"

* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
  i3c: dw: reduce do_daa time if there's no client
  i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
  i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
  i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
  i3c: dw: rename "pclk" to "apb" to match dt-binding
  i3c: dw: make struct dw_i3c_cmd smaller
  i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
  i3c: renesas: Don't register devices when ENTDAA times out
  i3c: master: dw-i3c-master: fix OD timing for first broadcast
  i3c: mipi-i3c-hci: Advertise IBI wakeup capability
  i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
  i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
  i3c: master: Reject IBI requests from non-IBI-capable devices
  i3c: master: Add helper to query bus wakeup requirements
  i3c: master: Report wakeup events for IBIs
  i3c: master: Support IBI-based wakeup capability
  i3c: master: Fix potential UAF in i3c_device_match()
  i3c: master: Fix potential UAF in i3c_device_uevent()
  i3c: Make dev->desc locking assumptions explicit
  i3c: master: Fix use-after-free of master->this
  ...

1 files changed, 225 insertions, 0 deletions

diff --git a/drivers/rtc/rtc-ds2404.c b/drivers/rtc/rtc-ds2404.c
new file mode 100644
index 000000000..217694eca
--- /dev/null
+++ b/drivers/rtc/rtc-ds2404.c
@@ -0,0 +1,225 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2012 Sven Schnelle <svens@stackframe.org>
+
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/rtc.h>
+#include <linux/types.h>
+#include <linux/bcd.h>
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/slab.h>
+
+#include <linux/io.h>
+
+#define DS2404_STATUS_REG 0x200
+#define DS2404_CONTROL_REG 0x201
+#define DS2404_RTC_REG 0x202
+
+#define DS2404_WRITE_SCRATCHPAD_CMD 0x0f
+#define DS2404_READ_SCRATCHPAD_CMD 0xaa
+#define DS2404_COPY_SCRATCHPAD_CMD 0x55
+#define DS2404_READ_MEMORY_CMD 0xf0
+
+#define DS2404_RST	0
+#define DS2404_CLK	1
+#define DS2404_DQ	2
+
+struct ds2404 {
+	struct device *dev;
+	struct gpio_desc *rst_gpiod;
+	struct gpio_desc *clk_gpiod;
+	struct gpio_desc *dq_gpiod;
+};
+
+static int ds2404_gpio_map(struct ds2404 *chip, struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+
+	/* This will de-assert RESET, declare this GPIO as GPIOD_ACTIVE_LOW */
+	chip->rst_gpiod = devm_gpiod_get(dev, "rst", GPIOD_OUT_LOW);
+	if (IS_ERR(chip->rst_gpiod))
+		return PTR_ERR(chip->rst_gpiod);
+
+	chip->clk_gpiod = devm_gpiod_get(dev, "clk", GPIOD_OUT_HIGH);
+	if (IS_ERR(chip->clk_gpiod))
+		return PTR_ERR(chip->clk_gpiod);
+
+	chip->dq_gpiod = devm_gpiod_get(dev, "dq", GPIOD_ASIS);
+	if (IS_ERR(chip->dq_gpiod))
+		return PTR_ERR(chip->dq_gpiod);
+
+	return 0;
+}
+
+static void ds2404_reset(struct ds2404 *chip)
+{
+	gpiod_set_value(chip->rst_gpiod, 1);
+	udelay(1000);
+	gpiod_set_value(chip->rst_gpiod, 0);
+	gpiod_set_value(chip->clk_gpiod, 0);
+	gpiod_direction_output(chip->dq_gpiod, 0);
+	udelay(10);
+}
+
+static void ds2404_write_byte(struct ds2404 *chip, u8 byte)
+{
+	int i;
+
+	gpiod_direction_output(chip->dq_gpiod, 1);
+	for (i = 0; i < 8; i++) {
+		gpiod_set_value(chip->dq_gpiod, byte & (1 << i));
+		udelay(10);
+		gpiod_set_value(chip->clk_gpiod, 1);
+		udelay(10);
+		gpiod_set_value(chip->clk_gpiod, 0);
+		udelay(10);
+	}
+}
+
+static u8 ds2404_read_byte(struct ds2404 *chip)
+{
+	int i;
+	u8 ret = 0;
+
+	gpiod_direction_input(chip->dq_gpiod);
+
+	for (i = 0; i < 8; i++) {
+		gpiod_set_value(chip->clk_gpiod, 0);
+		udelay(10);
+		if (gpiod_get_value(chip->dq_gpiod))
+			ret |= 1 << i;
+		gpiod_set_value(chip->clk_gpiod, 1);
+		udelay(10);
+	}
+	return ret;
+}
+
+static void ds2404_read_memory(struct ds2404 *chip, u16 offset,
+			       int length, u8 *out)
+{
+	ds2404_reset(chip);
+	ds2404_write_byte(chip, DS2404_READ_MEMORY_CMD);
+	ds2404_write_byte(chip, offset & 0xff);
+	ds2404_write_byte(chip, (offset >> 8) & 0xff);
+	while (length--)
+		*out++ = ds2404_read_byte(chip);
+}
+
+static void ds2404_write_memory(struct ds2404 *chip, u16 offset,
+				int length, u8 *out)
+{
+	int i;
+	u8 ta01, ta02, es;
+
+	ds2404_reset(chip);
+	ds2404_write_byte(chip, DS2404_WRITE_SCRATCHPAD_CMD);
+	ds2404_write_byte(chip, offset & 0xff);
+	ds2404_write_byte(chip, (offset >> 8) & 0xff);
+
+	for (i = 0; i < length; i++)
+		ds2404_write_byte(chip, out[i]);
+
+	ds2404_reset(chip);
+	ds2404_write_byte(chip, DS2404_READ_SCRATCHPAD_CMD);
+
+	ta01 = ds2404_read_byte(chip);
+	ta02 = ds2404_read_byte(chip);
+	es = ds2404_read_byte(chip);
+
+	for (i = 0; i < length; i++) {
+		if (out[i] != ds2404_read_byte(chip)) {
+			dev_err(chip->dev, "read invalid data\n");
+			return;
+		}
+	}
+
+	ds2404_reset(chip);
+	ds2404_write_byte(chip, DS2404_COPY_SCRATCHPAD_CMD);
+	ds2404_write_byte(chip, ta01);
+	ds2404_write_byte(chip, ta02);
+	ds2404_write_byte(chip, es);
+
+	while (gpiod_get_value(chip->dq_gpiod))
+		;
+}
+
+static void ds2404_enable_osc(struct ds2404 *chip)
+{
+	u8 in[1] = { 0x10 }; /* enable oscillator */
+
+	ds2404_write_memory(chip, 0x201, 1, in);
+}
+
+static int ds2404_read_time(struct device *dev, struct rtc_time *dt)
+{
+	struct ds2404 *chip = dev_get_drvdata(dev);
+	unsigned long time = 0;
+	__le32 hw_time = 0;
+
+	ds2404_read_memory(chip, 0x203, 4, (u8 *)&hw_time);
+	time = le32_to_cpu(hw_time);
+
+	rtc_time64_to_tm(time, dt);
+	return 0;
+}
+
+static int ds2404_set_time(struct device *dev, struct rtc_time *dt)
+{
+	struct ds2404 *chip = dev_get_drvdata(dev);
+	u32 time = cpu_to_le32(rtc_tm_to_time64(dt));
+	ds2404_write_memory(chip, 0x203, 4, (u8 *)&time);
+	return 0;
+}
+
+static const struct rtc_class_ops ds2404_rtc_ops = {
+	.read_time	= ds2404_read_time,
+	.set_time	= ds2404_set_time,
+};
+
+static int rtc_probe(struct platform_device *pdev)
+{
+	struct ds2404 *chip;
+	struct rtc_device *rtc;
+	int retval = -EBUSY;
+
+	chip = devm_kzalloc(&pdev->dev, sizeof(struct ds2404), GFP_KERNEL);
+	if (!chip)
+		return -ENOMEM;
+
+	chip->dev = &pdev->dev;
+
+	rtc = devm_rtc_allocate_device(&pdev->dev);
+	if (IS_ERR(rtc))
+		return PTR_ERR(rtc);
+
+	retval = ds2404_gpio_map(chip, pdev);
+	if (retval)
+		return retval;
+
+	platform_set_drvdata(pdev, chip);
+
+	rtc->ops = &ds2404_rtc_ops;
+	rtc->range_max = U32_MAX;
+
+	retval = devm_rtc_register_device(rtc);
+	if (retval)
+		return retval;
+
+	ds2404_enable_osc(chip);
+	return 0;
+}
+
+static struct platform_driver rtc_device_driver = {
+	.probe	= rtc_probe,
+	.driver = {
+		.name	= "ds2404",
+	},
+};
+module_platform_driver(rtc_device_driver);
+
+MODULE_DESCRIPTION("DS2404 RTC");
+MODULE_AUTHOR("Sven Schnelle");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:ds2404");