Prepare the function interface of the ihs_i2c driver for DM conversion
in a future patch.
While we're at it, fix some style violations, and make the code more readable.
Signed-off-by: Mario Six <mario....@gdsys.cc>
---
drivers/i2c/ihs_i2c.c | 74 +++++++++++++++++++++++++++++++--------------------
1 file changed, 45 insertions(+), 29 deletions(-)
diff --git a/drivers/i2c/ihs_i2c.c b/drivers/i2c/ihs_i2c.c
index 29612e69fe..e066ad53db 100644
--- a/drivers/i2c/ihs_i2c.c
+++ b/drivers/i2c/ihs_i2c.c
@@ -41,30 +41,38 @@ DECLARE_GLOBAL_DATA_PTR;
#endif
enum {
- I2CINT_ERROR_EV = 1 << 13,
- I2CINT_TRANSMIT_EV = 1 << 14,
- I2CINT_RECEIVE_EV = 1 << 15,
+ I2CINT_ERROR_EV = BIT(13),
+ I2CINT_TRANSMIT_EV = BIT(14),
+ I2CINT_RECEIVE_EV = BIT(15),
};
enum {
+ I2CMB_READ = 0 << 10,
I2CMB_WRITE = 1 << 10,
+ I2CMB_1BYTE = 0 << 11,
I2CMB_2BYTE = 1 << 11,
+ I2CMB_DONT_HOLD_BUS = 0 << 13,
I2CMB_HOLD_BUS = 1 << 13,
I2CMB_NATIVE = 2 << 14,
};
+enum {
+ I2COP_WRITE = 0,
+ I2COP_READ = 1,
+};
+
static int wait_for_int(bool read)
{
u16 val;
- unsigned int ctr = 0;
+ uint ctr = 0;
I2C_GET_REG(interrupt_status, &val);
+ /* Wait until error or receive/transmit interrupt was raised */
while (!(val & (I2CINT_ERROR_EV
| (read ? I2CINT_RECEIVE_EV : I2CINT_TRANSMIT_EV)))) {
udelay(10);
- if (ctr++ > 5000) {
+ if (ctr++ > 5000)
return 1;
- }
I2C_GET_REG(interrupt_status, &val);
}
@@ -76,10 +84,12 @@ static int ihs_i2c_transfer(uchar chip, uchar *buffer, int
len, bool read,
{
u16 val;
+ /* Clear interrupt status */
I2C_SET_REG(interrupt_status, I2CINT_ERROR_EV
| I2CINT_RECEIVE_EV | I2CINT_TRANSMIT_EV);
I2C_GET_REG(interrupt_status, &val);
+ /* If we want to write and have data, write the bytes to the mailbox */
if (!read && len) {
val = buffer[0];
@@ -98,6 +108,7 @@ static int ihs_i2c_transfer(uchar chip, uchar *buffer, int
len, bool read,
if (wait_for_int(read))
return 1;
+ /* If we want to read, get the bytes from the mailbox */
if (read) {
I2C_GET_REG(read_mailbox_ext, &val);
buffer[0] = val & 0xff;
@@ -108,55 +119,44 @@ static int ihs_i2c_transfer(uchar chip, uchar *buffer,
int len, bool read,
return 0;
}
-static int ihs_i2c_address(uchar chip, uint addr, int alen, bool hold_bus)
+static int ihs_i2c_address(uchar chip, u8 *addr, int alen, bool hold_bus)
{
- int shift = (alen-1) * 8;
-
while (alen) {
int transfer = min(alen, 2);
- uchar buf[2];
bool is_last = alen <= transfer;
- buf[0] = addr >> shift;
- if (alen > 1)
- buf[1] = addr >> (shift - 8);
-
- if (ihs_i2c_transfer(chip, buf, transfer, false,
+ if (ihs_i2c_transfer(chip, addr, transfer, I2COP_WRITE,
hold_bus ? false : is_last))
return 1;
- shift -= 16;
alen -= transfer;
}
return 0;
}
-static int ihs_i2c_access(struct i2c_adapter *adap, uchar chip, uint addr,
- int alen, uchar *buffer, int len, bool read)
+static int ihs_i2c_access(struct i2c_adapter *adap, uchar chip, u8 *addr,
+ int alen, uchar *buffer, int len, int read)
{
- if (len <= 0)
- return 1;
-
- if (ihs_i2c_address(chip, addr, alen, len))
+ /* Don't hold the bus if length of data to send/receive is zero */
+ if (len <= 0 || ihs_i2c_address(chip, addr, alen, len))
return 1;
while (len) {
int transfer = min(len, 2);
+ bool is_last = len <= transfer;
if (ihs_i2c_transfer(chip, buffer, transfer, read,
- len <= transfer))
- return 1;
+ is_last))
+ return 2;
buffer += transfer;
- addr += transfer;
len -= transfer;
}
return 0;
}
-
static void ihs_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
{
#ifdef CONFIG_SYS_I2C_INIT_BOARD
@@ -173,7 +173,7 @@ static int ihs_i2c_probe(struct i2c_adapter *adap, uchar
chip)
{
uchar buffer[2];
- if (ihs_i2c_transfer(chip, buffer, 0, true, true))
+ if (ihs_i2c_transfer(chip, buffer, 0, I2COP_READ, true))
return 1;
return 0;
@@ -182,13 +182,29 @@ static int ihs_i2c_probe(struct i2c_adapter *adap, uchar
chip)
static int ihs_i2c_read(struct i2c_adapter *adap, uchar chip, uint addr,
int alen, uchar *buffer, int len)
{
- return ihs_i2c_access(adap, chip, addr, alen, buffer, len, true);
+ u8 addr_bytes[4];
+
+ addr_bytes[0] = (addr >> 0) & 0xFF;
+ addr_bytes[1] = (addr >> 8) & 0xFF;
+ addr_bytes[2] = (addr >> 16) & 0xFF;
+ addr_bytes[3] = (addr >> 24) & 0xFF;
+
+ return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
+ I2COP_READ);
}
static int ihs_i2c_write(struct i2c_adapter *adap, uchar chip, uint addr,
int alen, uchar *buffer, int len)
{
- return ihs_i2c_access(adap, chip, addr, alen, buffer, len, false);
+ u8 addr_bytes[4];
+
+ addr_bytes[0] = (addr >> 0) & 0xFF;
+ addr_bytes[1] = (addr >> 8) & 0xFF;
+ addr_bytes[2] = (addr >> 16) & 0xFF;
+ addr_bytes[3] = (addr >> 24) & 0xFF;
+
+ return ihs_i2c_access(adap, chip, addr_bytes, alen, buffer, len,
+ I2COP_WRITE);
}
static unsigned int ihs_i2c_set_bus_speed(struct i2c_adapter *adap,
--
2.11.0
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