Merge tag 'char-misc-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

Pull char/misc updates from Greg KH:
 "Here is the big set of char/misc driver patches for 4.17-rc1.

  There are a lot of little things in here, nothing huge, but all
  important to the different hardware types involved:

   -  thunderbolt driver updates

   -  parport updates (people still care...)

   -  nvmem driver updates

   -  mei updates (as always)

   -  hwtracing driver updates

   -  hyperv driver updates

   -  extcon driver updates

   -  ... and a handful of even smaller driver subsystem and individual
      driver updates

  All of these have been in linux-next with no reported issues"

* tag 'char-misc-4.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (149 commits)
  hwtracing: Add HW tracing support menu
  intel_th: Add ACPI glue layer
  intel_th: Allow forcing host mode through drvdata
  intel_th: Pick up irq number from resources
  intel_th: Don't touch switch routing in host mode
  intel_th: Use correct method of finding hub
  intel_th: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate
  stm class: Make dummy's master/channel ranges configurable
  stm class: Add SPDX GPL-2.0 header to replace GPLv2 boilerplate
  MAINTAINERS: Bestow upon myself the care for drivers/hwtracing
  hv: add SPDX license id to Kconfig
  hv: add SPDX license to trace
  Drivers: hv: vmbus: do not mark HV_PCIE as perf_device
  Drivers: hv: vmbus: respect what we get from hv_get_synint_state()
  /dev/mem: Avoid overwriting "err" in read_mem()
  eeprom: at24: use SPDX identifier instead of GPL boiler-plate
  eeprom: at24: simplify the i2c functionality checking
  eeprom: at24: fix a line break
  eeprom: at24: tweak newlines
  eeprom: at24: refactor at24_probe()
  ...

1 files changed, 87 insertions, 2 deletions

diff --git a/drivers/fsi/fsi-master-gpio.c b/drivers/fsi/fsi-master-gpio.c
index ae2618768508..3f487449a277 100644
--- a/drivers/fsi/fsi-master-gpio.c
+++ b/drivers/fsi/fsi-master-gpio.c
@@ -9,6 +9,7 @@
 #include <linux/gpio/consumer.h>
 #include <linux/io.h>
 #include <linux/module.h>
+#include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
@@ -59,6 +60,7 @@ struct fsi_master_gpio {
 	struct gpio_desc	*gpio_trans;	/* Voltage translator */
 	struct gpio_desc	*gpio_enable;	/* FSI enable */
 	struct gpio_desc	*gpio_mux;	/* Mux control */
+	bool			external_mode;
 };
 
 #define CREATE_TRACE_POINTS
@@ -411,6 +413,12 @@ static int fsi_master_gpio_xfer(struct fsi_master_gpio *master, uint8_t slave,
 	int rc;
 
 	spin_lock_irqsave(&master->cmd_lock, flags);
+
+	if (master->external_mode) {
+		spin_unlock_irqrestore(&master->cmd_lock, flags);
+		return -EBUSY;
+	}
+
 	serial_out(master, cmd);
 	echo_delay(master);
 	rc = poll_for_response(master, slave, resp_len, resp);
@@ -461,12 +469,18 @@ static int fsi_master_gpio_term(struct fsi_master *_master,
 static int fsi_master_gpio_break(struct fsi_master *_master, int link)
 {
 	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
+	unsigned long flags;
 
 	if (link != 0)
 		return -ENODEV;
 
 	trace_fsi_master_gpio_break(master);
 
+	spin_lock_irqsave(&master->cmd_lock, flags);
+	if (master->external_mode) {
+		spin_unlock_irqrestore(&master->cmd_lock, flags);
+		return -EBUSY;
+	}
 	set_sda_output(master, 1);
 	sda_out(master, 1);
 	clock_toggle(master, FSI_PRE_BREAK_CLOCKS);
@@ -475,6 +489,7 @@ static int fsi_master_gpio_break(struct fsi_master *_master, int link)
 	echo_delay(master);
 	sda_out(master, 1);
 	clock_toggle(master, FSI_POST_BREAK_CLOCKS);
+	spin_unlock_irqrestore(&master->cmd_lock, flags);
 
 	/* Wait for logic reset to take effect */
 	udelay(200);
@@ -494,21 +509,84 @@ static void fsi_master_gpio_init(struct fsi_master_gpio *master)
 	clock_zeros(master, FSI_INIT_CLOCKS);
 }
 
+static void fsi_master_gpio_init_external(struct fsi_master_gpio *master)
+{
+	gpiod_direction_output(master->gpio_mux, 0);
+	gpiod_direction_output(master->gpio_trans, 0);
+	gpiod_direction_output(master->gpio_enable, 1);
+	gpiod_direction_input(master->gpio_clk);
+	gpiod_direction_input(master->gpio_data);
+}
+
 static int fsi_master_gpio_link_enable(struct fsi_master *_master, int link)
 {
 	struct fsi_master_gpio *master = to_fsi_master_gpio(_master);
+	unsigned long flags;
+	int rc = -EBUSY;
 
 	if (link != 0)
 		return -ENODEV;
-	gpiod_set_value(master->gpio_enable, 1);
 
-	return 0;
+	spin_lock_irqsave(&master->cmd_lock, flags);
+	if (!master->external_mode) {
+		gpiod_set_value(master->gpio_enable, 1);
+		rc = 0;
+	}
+	spin_unlock_irqrestore(&master->cmd_lock, flags);
+
+	return rc;
+}
+
+static ssize_t external_mode_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct fsi_master_gpio *master = dev_get_drvdata(dev);
+
+	return snprintf(buf, PAGE_SIZE - 1, "%u\n",
+			master->external_mode ? 1 : 0);
 }
 
+static ssize_t external_mode_store(struct device *dev,
+		struct device_attribute *attr, const char *buf, size_t count)
+{
+	struct fsi_master_gpio *master = dev_get_drvdata(dev);
+	unsigned long flags, val;
+	bool external_mode;
+	int err;
+
+	err = kstrtoul(buf, 0, &val);
+	if (err)
+		return err;
+
+	external_mode = !!val;
+
+	spin_lock_irqsave(&master->cmd_lock, flags);
+
+	if (external_mode == master->external_mode) {
+		spin_unlock_irqrestore(&master->cmd_lock, flags);
+		return count;
+	}
+
+	master->external_mode = external_mode;
+	if (master->external_mode)
+		fsi_master_gpio_init_external(master);
+	else
+		fsi_master_gpio_init(master);
+	spin_unlock_irqrestore(&master->cmd_lock, flags);
+
+	fsi_master_rescan(&master->master);
+
+	return count;
+}
+
+static DEVICE_ATTR(external_mode, 0664,
+		external_mode_show, external_mode_store);
+
 static int fsi_master_gpio_probe(struct platform_device *pdev)
 {
 	struct fsi_master_gpio *master;
 	struct gpio_desc *gpio;
+	int rc;
 
 	master = devm_kzalloc(&pdev->dev, sizeof(*master), GFP_KERNEL);
 	if (!master)
@@ -516,6 +594,7 @@ static int fsi_master_gpio_probe(struct platform_device *pdev)
 
 	master->dev = &pdev->dev;
 	master->master.dev.parent = master->dev;
+	master->master.dev.of_node = of_node_get(dev_of_node(master->dev));
 
 	gpio = devm_gpiod_get(&pdev->dev, "clock", 0);
 	if (IS_ERR(gpio)) {
@@ -565,6 +644,10 @@ static int fsi_master_gpio_probe(struct platform_device *pdev)
 
 	fsi_master_gpio_init(master);
 
+	rc = device_create_file(&pdev->dev, &dev_attr_external_mode);
+	if (rc)
+		return rc;
+
 	return fsi_master_register(&master->master);
 }
 
@@ -583,6 +666,8 @@ static int fsi_master_gpio_remove(struct platform_device *pdev)
 		devm_gpiod_put(&pdev->dev, master->gpio_mux);
 	fsi_master_unregister(&master->master);
 
+	of_node_put(master->master.dev.of_node);
+
 	return 0;
 }