Merge branch 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux

Pull i2c updates from Wolfram Sang:
 "I2C has the following changes for you:

   - new flag to mark DMA safe buffers in i2c_msg. Also, some
     infrastructure around it. And docs.

   - huge refactoring of the at24 driver led by the new maintainer
     Bartosz

   - update I2C bus recovery to send STOP after recovery

   - conversion from gpio to gpiod for I2C bus recovery

   - adding a fault-injector to the i2c-gpio driver

   - lots of small driver improvements, and bigger ones to
     i2c-sh_mobile"

* 'i2c/for-4.16' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (99 commits)
  i2c: mv64xxx: Add myself as maintainer for this driver
  i2c: mv64xxx: Fix clock resource by adding an optional bus clock
  i2c: mv64xxx: Remove useless test before clk_disable_unprepare
  i2c: mxs: use true and false for boolean values
  i2c: meson: update doc description to fix build warnings
  i2c: meson: add configurable divider factors
  dt-bindings: i2c: update documentation for the Meson-AXG
  i2c: imx-lpi2c: add runtime pm support
  i2c: rcar: fix some trivial typos in comments
  i2c: davinci: fix the cpufreq transition
  i2c: rk3x: add proper kerneldoc header
  i2c: rk3x: account for const type of of_device_id.data
  i2c: acorn: remove outdated path from file header
  i2c: acorn: add MODULE_LICENSE tag
  i2c: rcar: implement bus recovery
  i2c: send STOP after successful bus recovery
  i2c: ensure SDA is released in recovery if SDA is controllable
  i2c: add 'set_sda' to bus_recovery_info
  i2c: add identifier in declarations for i2c_bus_recovery
  i2c: make kerneldoc about bus recovery more precise
  ...

4 files changed, 95 insertions, 27 deletions

diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 0f774406fad0..419a38e7c315 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -55,7 +55,7 @@ typedef int (*i2c_slave_cb_t)(struct i2c_client *, enum i2c_slave_event, u8 *);
 struct module;
 struct property_entry;
 
-#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
+#if IS_ENABLED(CONFIG_I2C)
 /*
  * The master routines are the ones normally used to transmit data to devices
  * on a bus (or read from them). Apart from two basic transfer functions to
@@ -63,10 +63,68 @@ struct property_entry;
  * transmit an arbitrary number of messages without interruption.
  * @count must be be less than 64k since msg.len is u16.
  */
-extern int i2c_master_send(const struct i2c_client *client, const char *buf,
-			   int count);
-extern int i2c_master_recv(const struct i2c_client *client, char *buf,
-			   int count);
+extern int i2c_transfer_buffer_flags(const struct i2c_client *client,
+				     char *buf, int count, u16 flags);
+
+/**
+ * i2c_master_recv - issue a single I2C message in master receive mode
+ * @client: Handle to slave device
+ * @buf: Where to store data read from slave
+ * @count: How many bytes to read, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes read.
+ */
+static inline int i2c_master_recv(const struct i2c_client *client,
+				  char *buf, int count)
+{
+	return i2c_transfer_buffer_flags(client, buf, count, I2C_M_RD);
+};
+
+/**
+ * i2c_master_recv_dmasafe - issue a single I2C message in master receive mode
+ *			     using a DMA safe buffer
+ * @client: Handle to slave device
+ * @buf: Where to store data read from slave, must be safe to use with DMA
+ * @count: How many bytes to read, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes read.
+ */
+static inline int i2c_master_recv_dmasafe(const struct i2c_client *client,
+					  char *buf, int count)
+{
+	return i2c_transfer_buffer_flags(client, buf, count,
+					 I2C_M_RD | I2C_M_DMA_SAFE);
+};
+
+/**
+ * i2c_master_send - issue a single I2C message in master transmit mode
+ * @client: Handle to slave device
+ * @buf: Data that will be written to the slave
+ * @count: How many bytes to write, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes written.
+ */
+static inline int i2c_master_send(const struct i2c_client *client,
+				  const char *buf, int count)
+{
+	return i2c_transfer_buffer_flags(client, (char *)buf, count, 0);
+};
+
+/**
+ * i2c_master_send_dmasafe - issue a single I2C message in master transmit mode
+ *			     using a DMA safe buffer
+ * @client: Handle to slave device
+ * @buf: Data that will be written to the slave, must be safe to use with DMA
+ * @count: How many bytes to write, must be less than 64k since msg.len is u16
+ *
+ * Returns negative errno, or else the number of bytes written.
+ */
+static inline int i2c_master_send_dmasafe(const struct i2c_client *client,
+					  const char *buf, int count)
+{
+	return i2c_transfer_buffer_flags(client, (char *)buf, count,
+					 I2C_M_DMA_SAFE);
+};
 
 /* Transfer num messages.
  */
@@ -354,7 +412,7 @@ struct i2c_board_info {
 	.type = dev_type, .addr = (dev_addr)
 
 
-#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
+#if IS_ENABLED(CONFIG_I2C)
 /* Add-on boards should register/unregister their devices; e.g. a board
  * with integrated I2C, a config eeprom, sensors, and a codec that's
  * used in conjunction with the primary hardware.
@@ -485,40 +543,43 @@ struct i2c_timings {
 /**
  * struct i2c_bus_recovery_info - I2C bus recovery information
  * @recover_bus: Recover routine. Either pass driver's recover_bus() routine, or
- *	i2c_generic_scl_recovery() or i2c_generic_gpio_recovery().
+ *	i2c_generic_scl_recovery().
  * @get_scl: This gets current value of SCL line. Mandatory for generic SCL
- *      recovery. Used internally for generic GPIO recovery.
- * @set_scl: This sets/clears SCL line. Mandatory for generic SCL recovery. Used
- *      internally for generic GPIO recovery.
+ *      recovery. Populated internally for generic GPIO recovery.
+ * @set_scl: This sets/clears the SCL line. Mandatory for generic SCL recovery.
+ *      Populated internally for generic GPIO recovery.
  * @get_sda: This gets current value of SDA line. Optional for generic SCL
- *      recovery. Used internally, if sda_gpio is a valid GPIO, for generic GPIO
- *      recovery.
+ *      recovery. Populated internally, if sda_gpio is a valid GPIO, for generic
+ *      GPIO recovery.
+ * @set_sda: This sets/clears the SDA line. Optional for generic SCL recovery.
+ *	Populated internally, if sda_gpio is a valid GPIO, for generic GPIO
+ *	recovery.
  * @prepare_recovery: This will be called before starting recovery. Platform may
  *	configure padmux here for SDA/SCL line or something else they want.
  * @unprepare_recovery: This will be called after completing recovery. Platform
  *	may configure padmux here for SDA/SCL line or something else they want.
- * @scl_gpio: gpio number of the SCL line. Only required for GPIO recovery.
- * @sda_gpio: gpio number of the SDA line. Only required for GPIO recovery.
+ * @scl_gpiod: gpiod of the SCL line. Only required for GPIO recovery.
+ * @sda_gpiod: gpiod of the SDA line. Only required for GPIO recovery.
  */
 struct i2c_bus_recovery_info {
-	int (*recover_bus)(struct i2c_adapter *);
+	int (*recover_bus)(struct i2c_adapter *adap);
 
-	int (*get_scl)(struct i2c_adapter *);
-	void (*set_scl)(struct i2c_adapter *, int val);
-	int (*get_sda)(struct i2c_adapter *);
+	int (*get_scl)(struct i2c_adapter *adap);
+	void (*set_scl)(struct i2c_adapter *adap, int val);
+	int (*get_sda)(struct i2c_adapter *adap);
+	void (*set_sda)(struct i2c_adapter *adap, int val);
 
-	void (*prepare_recovery)(struct i2c_adapter *);
-	void (*unprepare_recovery)(struct i2c_adapter *);
+	void (*prepare_recovery)(struct i2c_adapter *adap);
+	void (*unprepare_recovery)(struct i2c_adapter *adap);
 
 	/* gpio recovery */
-	int scl_gpio;
-	int sda_gpio;
+	struct gpio_desc *scl_gpiod;
+	struct gpio_desc *sda_gpiod;
 };
 
 int i2c_recover_bus(struct i2c_adapter *adap);
 
 /* Generic recovery routines */
-int i2c_generic_gpio_recovery(struct i2c_adapter *adap);
 int i2c_generic_scl_recovery(struct i2c_adapter *adap);
 
 /**
@@ -706,7 +767,7 @@ i2c_unlock_adapter(struct i2c_adapter *adapter)
 
 /* administration...
  */
-#if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE)
+#if IS_ENABLED(CONFIG_I2C)
 extern int i2c_add_adapter(struct i2c_adapter *);
 extern void i2c_del_adapter(struct i2c_adapter *);
 extern int i2c_add_numbered_adapter(struct i2c_adapter *);
@@ -769,6 +830,9 @@ static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg)
 	return (msg->addr << 1) | (msg->flags & I2C_M_RD ? 1 : 0);
 }
 
+u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold);
+void i2c_release_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf);
+
 int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr);
 /**
  * module_i2c_driver() - Helper macro for registering a modular I2C driver
diff --git a/include/linux/platform_data/at24.h b/include/linux/platform_data/at24.h
index 271a4e25af67..63507ff464ee 100644
--- a/include/linux/platform_data/at24.h
+++ b/include/linux/platform_data/at24.h
@@ -50,6 +50,8 @@ struct at24_platform_data {
 #define AT24_FLAG_TAKE8ADDR	BIT(4)	/* take always 8 addresses (24c00) */
 #define AT24_FLAG_SERIAL	BIT(3)	/* factory-programmed serial number */
 #define AT24_FLAG_MAC		BIT(2)	/* factory-programmed mac address */
+#define AT24_FLAG_NO_RDROL	BIT(1)	/* does not auto-rollover reads to */
+					/* the next slave address */
 
 	void		(*setup)(struct nvmem_device *nvmem, void *context);
 	void		*context;
diff --git a/include/linux/platform_data/i2c-davinci.h b/include/linux/platform_data/i2c-davinci.h
index 89fd34727a24..98967df07468 100644
--- a/include/linux/platform_data/i2c-davinci.h
+++ b/include/linux/platform_data/i2c-davinci.h
@@ -16,9 +16,8 @@
 struct davinci_i2c_platform_data {
 	unsigned int	bus_freq;	/* standard bus frequency (kHz) */
 	unsigned int	bus_delay;	/* post-transaction delay (usec) */
-	unsigned int    sda_pin;        /* GPIO pin ID to use for SDA */
-	unsigned int    scl_pin;        /* GPIO pin ID to use for SCL */
-	bool		has_pfunc;	/*chip has a ICPFUNC register */
+	bool		gpio_recovery;	/* Use GPIO recovery method */
+	bool		has_pfunc;	/* Chip has a ICPFUNC register */
 };
 
 /* for board setup code */
diff --git a/include/uapi/linux/i2c.h b/include/uapi/linux/i2c.h
index fe648032d6b9..f71a1751cacf 100644
--- a/include/uapi/linux/i2c.h
+++ b/include/uapi/linux/i2c.h
@@ -72,6 +72,9 @@ struct i2c_msg {
 #define I2C_M_RD		0x0001	/* read data, from slave to master */
 					/* I2C_M_RD is guaranteed to be 0x0001! */
 #define I2C_M_TEN		0x0010	/* this is a ten bit chip address */
+#define I2C_M_DMA_SAFE		0x0200	/* the buffer of this message is DMA safe */
+					/* makes only sense in kernelspace */
+					/* userspace buffers are copied anyway */
 #define I2C_M_RECV_LEN		0x0400	/* length will be first received byte */
 #define I2C_M_NO_RD_ACK		0x0800	/* if I2C_FUNC_PROTOCOL_MANGLING */
 #define I2C_M_IGNORE_NAK	0x1000	/* if I2C_FUNC_PROTOCOL_MANGLING */