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-rw-r--r--include/linux/i2c.h55
-rw-r--r--include/linux/of.h6
-rw-r--r--include/linux/platform_data/i2c-davinci.h1
3 files changed, 56 insertions, 6 deletions
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index f17da50402a4..898033f41d76 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -253,10 +253,10 @@ static inline void i2c_set_clientdata(struct i2c_client *dev, void *data)
#if IS_ENABLED(CONFIG_I2C_SLAVE)
enum i2c_slave_event {
- I2C_SLAVE_REQ_READ_START,
- I2C_SLAVE_REQ_READ_END,
- I2C_SLAVE_REQ_WRITE_START,
- I2C_SLAVE_REQ_WRITE_END,
+ I2C_SLAVE_READ_REQUESTED,
+ I2C_SLAVE_WRITE_REQUESTED,
+ I2C_SLAVE_READ_PROCESSED,
+ I2C_SLAVE_WRITE_RECEIVED,
I2C_SLAVE_STOP,
};
@@ -435,8 +435,8 @@ struct i2c_bus_recovery_info {
void (*set_scl)(struct i2c_adapter *, int val);
int (*get_sda)(struct i2c_adapter *);
- void (*prepare_recovery)(struct i2c_bus_recovery_info *bri);
- void (*unprepare_recovery)(struct i2c_bus_recovery_info *bri);
+ void (*prepare_recovery)(struct i2c_adapter *);
+ void (*unprepare_recovery)(struct i2c_adapter *);
/* gpio recovery */
int scl_gpio;
@@ -449,6 +449,48 @@ int i2c_recover_bus(struct i2c_adapter *adap);
int i2c_generic_gpio_recovery(struct i2c_adapter *adap);
int i2c_generic_scl_recovery(struct i2c_adapter *adap);
+/**
+ * struct i2c_adapter_quirks - describe flaws of an i2c adapter
+ * @flags: see I2C_AQ_* for possible flags and read below
+ * @max_num_msgs: maximum number of messages per transfer
+ * @max_write_len: maximum length of a write message
+ * @max_read_len: maximum length of a read message
+ * @max_comb_1st_msg_len: maximum length of the first msg in a combined message
+ * @max_comb_2nd_msg_len: maximum length of the second msg in a combined message
+ *
+ * Note about combined messages: Some I2C controllers can only send one message
+ * per transfer, plus something called combined message or write-then-read.
+ * This is (usually) a small write message followed by a read message and
+ * barely enough to access register based devices like EEPROMs. There is a flag
+ * to support this mode. It implies max_num_msg = 2 and does the length checks
+ * with max_comb_*_len because combined message mode usually has its own
+ * limitations. Because of HW implementations, some controllers can actually do
+ * write-then-anything or other variants. To support that, write-then-read has
+ * been broken out into smaller bits like write-first and read-second which can
+ * be combined as needed.
+ */
+
+struct i2c_adapter_quirks {
+ u64 flags;
+ int max_num_msgs;
+ u16 max_write_len;
+ u16 max_read_len;
+ u16 max_comb_1st_msg_len;
+ u16 max_comb_2nd_msg_len;
+};
+
+/* enforce max_num_msgs = 2 and use max_comb_*_len for length checks */
+#define I2C_AQ_COMB BIT(0)
+/* first combined message must be write */
+#define I2C_AQ_COMB_WRITE_FIRST BIT(1)
+/* second combined message must be read */
+#define I2C_AQ_COMB_READ_SECOND BIT(2)
+/* both combined messages must have the same target address */
+#define I2C_AQ_COMB_SAME_ADDR BIT(3)
+/* convenience macro for typical write-then read case */
+#define I2C_AQ_COMB_WRITE_THEN_READ (I2C_AQ_COMB | I2C_AQ_COMB_WRITE_FIRST | \
+ I2C_AQ_COMB_READ_SECOND | I2C_AQ_COMB_SAME_ADDR)
+
/*
* i2c_adapter is the structure used to identify a physical i2c bus along
* with the access algorithms necessary to access it.
@@ -474,6 +516,7 @@ struct i2c_adapter {
struct list_head userspace_clients;
struct i2c_bus_recovery_info *bus_recovery_info;
+ const struct i2c_adapter_quirks *quirks;
};
#define to_i2c_adapter(d) container_of(d, struct i2c_adapter, dev)
diff --git a/include/linux/of.h b/include/linux/of.h
index dfde07e77a63..9bfcc18ceab3 100644
--- a/include/linux/of.h
+++ b/include/linux/of.h
@@ -332,6 +332,7 @@ extern int of_count_phandle_with_args(const struct device_node *np,
extern void of_alias_scan(void * (*dt_alloc)(u64 size, u64 align));
extern int of_alias_get_id(struct device_node *np, const char *stem);
+extern int of_alias_get_highest_id(const char *stem);
extern int of_machine_is_compatible(const char *compat);
@@ -594,6 +595,11 @@ static inline int of_alias_get_id(struct device_node *np, const char *stem)
return -ENOSYS;
}
+static inline int of_alias_get_highest_id(const char *stem)
+{
+ return -ENOSYS;
+}
+
static inline int of_machine_is_compatible(const char *compat)
{
return 0;
diff --git a/include/linux/platform_data/i2c-davinci.h b/include/linux/platform_data/i2c-davinci.h
index 2312d197dfb7..89fd34727a24 100644
--- a/include/linux/platform_data/i2c-davinci.h
+++ b/include/linux/platform_data/i2c-davinci.h
@@ -18,6 +18,7 @@ struct davinci_i2c_platform_data {
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 */
};
/* for board setup code */