This patch modifies the S3C I2C driver to suppport EXYNOS5. The cahnges made to driver are as follows: - I2C base address is passed as a parameter to many functions to avoid multiple #ifdef - Channel initialisation is moved to a commom funation as it is required by i2c_init. - Hardcoding for I2CCON_ACKGEN removed. - Replaced printf with debug. - Checkpatch issues resolved. - Pinmux setting will be done in board/samsung/smdk5250/smdk5250.c to avoid repeated setting of gpio lines, as it have multi bus support.
Signed-off-by: Alim Akhtar alim.akhtar@samsung.com Signed-off-by: Doug Anderson dianders@chromium.org Signed-off-by: Rajeshwari Shinde rajeshwari.s@samsung.com Acked-by: Simon Glass sjg@chromium.org --- Changes in V2: - Removed #define for I2C cahnnels from hearder file except for I2C0. - Incorporated review comments from Simon Glass. Changes in V3: - Incorporated review comments from Joonyoung Shim. - Reduced the number of #ifdef by modifying get_i2c_base function. - Removed duplicate code. Changes in V4: - Resolved build error for s3c2410. Changes in V5: - Pinmux setting will be done in board/samsung/smdk5250/smdk5250.c to avoid repeated setting of gpio lines, as it have multi bus support. - I2C bus offset calulation done based on EXYNOS_I2C_SPACING - Peripharal related code removed. Changes in V6: - g_current_bus made common to all platforms. drivers/i2c/s3c24x0_i2c.c | 193 +++++++++++++++++++++++++++----------------- 1 files changed, 118 insertions(+), 75 deletions(-)
diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c index ba6f39b..421c7dd 100644 --- a/drivers/i2c/s3c24x0_i2c.c +++ b/drivers/i2c/s3c24x0_i2c.c @@ -27,10 +27,15 @@ */
#include <common.h> +#ifdef CONFIG_EXYNOS5 +#include <asm/arch/clk.h> +#include <asm/arch/cpu.h> +#else #include <asm/arch/s3c24x0_cpu.h> - +#endif #include <asm/io.h> #include <i2c.h> +#include "s3c24x0_i2c.h"
#ifdef CONFIG_HARD_I2C
@@ -45,6 +50,7 @@
#define I2CSTAT_BSY 0x20 /* Busy bit */ #define I2CSTAT_NACK 0x01 /* Nack bit */ +#define I2CCON_ACKGEN 0x80 /* Acknowledge generation */ #define I2CCON_IRPND 0x10 /* Interrupt pending bit */ #define I2C_MODE_MT 0xC0 /* Master Transmit Mode */ #define I2C_MODE_MR 0x80 /* Master Receive Mode */ @@ -53,6 +59,10 @@
#define I2C_TIMEOUT 1 /* 1 second */
+ +static unsigned int g_current_bus; /* Stores Current I2C Bus */ + +#ifndef CONFIG_EXYNOS5 static int GetI2CSDA(void) { struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); @@ -77,16 +87,17 @@ static void SetI2CSCL(int x) struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio();
#ifdef CONFIG_S3C2410 - writel((readl(&gpio->gpedat) & ~0x4000) | (x & 1) << 14, &gpio->gpedat); + writel((readl(&gpio->gpedat) & ~0x4000) | + (x & 1) << 14, &gpio->gpedat); #endif #ifdef CONFIG_S3C2400 writel((readl(&gpio->pgdat) & ~0x0040) | (x & 1) << 6, &gpio->pgdat); #endif } +#endif
-static int WaitForXfer(void) +static int WaitForXfer(struct s3c24x0_i2c *i2c) { - struct s3c24x0_i2c *i2c = s3c24x0_get_base_i2c(); int i;
i = I2C_TIMEOUT * 10000; @@ -98,35 +109,77 @@ static int WaitForXfer(void) return (readl(&i2c->iiccon) & I2CCON_IRPND) ? I2C_OK : I2C_NOK_TOUT; }
-static int IsACK(void) +static int IsACK(struct s3c24x0_i2c *i2c) { - struct s3c24x0_i2c *i2c = s3c24x0_get_base_i2c(); - return !(readl(&i2c->iicstat) & I2CSTAT_NACK); }
-static void ReadWriteByte(void) +static void ReadWriteByte(struct s3c24x0_i2c *i2c) { - struct s3c24x0_i2c *i2c = s3c24x0_get_base_i2c(); - writel(readl(&i2c->iiccon) & ~I2CCON_IRPND, &i2c->iiccon); }
+static struct s3c24x0_i2c *get_base_i2c(void) +{ +#ifdef CONFIG_EXYNOS5 + struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)(samsung_get_base_i2c() + + (EXYNOS5_I2C_SPACING + * g_current_bus)); + return i2c; +#else + return s3c24x0_get_base_i2c(); +#endif +} + +static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd) +{ + ulong freq, pres = 16, div; +#ifdef CONFIG_EXYNOS5 + freq = get_i2c_clk(); +#else + freq = get_PCLK(); +#endif + /* calculate prescaler and divisor values */ + if ((freq / pres / (16 + 1)) > speed) + /* set prescaler to 512 */ + pres = 512; + + div = 0; + while ((freq / pres / (div + 1)) > speed) + div++; + + /* set prescaler, divisor according to freq, also set ACKGEN, IRQ */ + writel((div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0), &i2c->iiccon); + + /* init to SLAVE REVEIVE and set slaveaddr */ + writel(0, &i2c->iicstat); + writel(slaveadd, &i2c->iicadd); + /* program Master Transmit (and implicit STOP) */ + writel(I2C_MODE_MT | I2C_TXRX_ENA, &i2c->iicstat); +} + void i2c_init(int speed, int slaveadd) { - struct s3c24x0_i2c *i2c = s3c24x0_get_base_i2c(); + struct s3c24x0_i2c *i2c = get_base_i2c(); +#ifndef CONFIG_EXYNOS5 struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); - ulong freq, pres = 16, div; +#endif int i;
- /* wait for some time to give previous transfer a chance to finish */ + /* By default i2c channel 0 is the current bus */ + g_current_bus = 0;
+#ifdef CONFIG_EXYNOS5 + i2c_ch_init(i2c, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); +#endif + /* wait for some time to give previous transfer a chance to finish */ i = I2C_TIMEOUT * 1000; while ((readl(&i2c->iicstat) && I2CSTAT_BSY) && (i > 0)) { udelay(1000); i--; }
+#ifndef CONFIG_EXYNOS5 if ((readl(&i2c->iicstat) & I2CSTAT_BSY) || GetI2CSDA() == 0) { #ifdef CONFIG_S3C2410 ulong old_gpecon = readl(&gpio->gpecon); @@ -171,26 +224,8 @@ void i2c_init(int speed, int slaveadd) #endif }
- /* calculate prescaler and divisor values */ - freq = get_PCLK(); - if ((freq / pres / (16 + 1)) > speed) - /* set prescaler to 512 */ - pres = 512; - - div = 0; - while ((freq / pres / (div + 1)) > speed) - div++; - - /* set prescaler, divisor according to freq, also set - * ACKGEN, IRQ */ - writel((div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0), &i2c->iiccon); - - /* init to SLAVE REVEIVE and set slaveaddr */ - writel(0, &i2c->iicstat); - writel(slaveadd, &i2c->iicadd); - /* program Master Transmit (and implicit STOP) */ - writel(I2C_MODE_MT | I2C_TXRX_ENA, &i2c->iicstat); - + i2c_ch_init(i2c, speed, slaveadd); +#endif /* #ifndef CONFIG_EXYNOS5 */ }
/* @@ -200,19 +235,19 @@ void i2c_init(int speed, int slaveadd) * by the char, we could make it larger if needed. If it is * 0 we skip the address write cycle. */ -static -int i2c_transfer(unsigned char cmd_type, - unsigned char chip, - unsigned char addr[], - unsigned char addr_len, - unsigned char data[], unsigned short data_len) +static int i2c_transfer(struct s3c24x0_i2c *i2c, + unsigned char cmd_type, + unsigned char chip, + unsigned char addr[], + unsigned char addr_len, + unsigned char data[], + unsigned short data_len) { - struct s3c24x0_i2c *i2c = s3c24x0_get_base_i2c(); int i, result;
if (data == 0 || data_len == 0) { /*Don't support data transfer of no length or to address 0 */ - printf("i2c_transfer: bad call\n"); + debug("i2c_transfer: bad call\n"); return I2C_NOK; }
@@ -226,7 +261,7 @@ int i2c_transfer(unsigned char cmd_type, if (readl(&i2c->iicstat) & I2CSTAT_BSY) return I2C_NOK_TOUT;
- writel(readl(&i2c->iiccon) | 0x80, &i2c->iiccon); + writel(readl(&i2c->iiccon) | I2CCON_ACKGEN, &i2c->iiccon); result = I2C_OK;
switch (cmd_type) { @@ -238,16 +273,16 @@ int i2c_transfer(unsigned char cmd_type, &i2c->iicstat); i = 0; while ((i < addr_len) && (result == I2C_OK)) { - result = WaitForXfer(); + result = WaitForXfer(i2c); writel(addr[i], &i2c->iicds); - ReadWriteByte(); + ReadWriteByte(i2c); i++; } i = 0; while ((i < data_len) && (result == I2C_OK)) { - result = WaitForXfer(); + result = WaitForXfer(i2c); writel(data[i], &i2c->iicds); - ReadWriteByte(); + ReadWriteByte(i2c); i++; } } else { @@ -257,19 +292,19 @@ int i2c_transfer(unsigned char cmd_type, &i2c->iicstat); i = 0; while ((i < data_len) && (result = I2C_OK)) { - result = WaitForXfer(); + result = WaitForXfer(i2c); writel(data[i], &i2c->iicds); - ReadWriteByte(); + ReadWriteByte(i2c); i++; } }
if (result == I2C_OK) - result = WaitForXfer(); + result = WaitForXfer(i2c);
/* send STOP */ writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat); - ReadWriteByte(); + ReadWriteByte(i2c); break;
case I2C_READ: @@ -279,13 +314,13 @@ int i2c_transfer(unsigned char cmd_type, /* send START */ writel(readl(&i2c->iicstat) | I2C_START_STOP, &i2c->iicstat); - result = WaitForXfer(); - if (IsACK()) { + result = WaitForXfer(i2c); + if (IsACK(i2c)) { i = 0; while ((i < addr_len) && (result == I2C_OK)) { writel(addr[i], &i2c->iicds); - ReadWriteByte(); - result = WaitForXfer(); + ReadWriteByte(i2c); + result = WaitForXfer(i2c); i++; }
@@ -293,16 +328,17 @@ int i2c_transfer(unsigned char cmd_type, /* resend START */ writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP, &i2c->iicstat); - ReadWriteByte(); - result = WaitForXfer(); + ReadWriteByte(i2c); + result = WaitForXfer(i2c); i = 0; while ((i < data_len) && (result == I2C_OK)) { /* disable ACK for final READ */ if (i == data_len - 1) writel(readl(&i2c->iiccon) - & ~0x80, &i2c->iiccon); - ReadWriteByte(); - result = WaitForXfer(); + & ~I2CCON_ACKGEN, + &i2c->iiccon); + ReadWriteByte(i2c); + result = WaitForXfer(i2c); data[i] = readl(&i2c->iicds); i++; } @@ -316,17 +352,18 @@ int i2c_transfer(unsigned char cmd_type, /* send START */ writel(readl(&i2c->iicstat) | I2C_START_STOP, &i2c->iicstat); - result = WaitForXfer(); + result = WaitForXfer(i2c);
- if (IsACK()) { + if (IsACK(i2c)) { i = 0; while ((i < data_len) && (result == I2C_OK)) { /* disable ACK for final READ */ if (i == data_len - 1) writel(readl(&i2c->iiccon) & - ~0x80, &i2c->iiccon); - ReadWriteByte(); - result = WaitForXfer(); + ~I2CCON_ACKGEN, + &i2c->iiccon); + ReadWriteByte(i2c); + result = WaitForXfer(i2c); data[i] = readl(&i2c->iicds); i++; } @@ -337,22 +374,24 @@ int i2c_transfer(unsigned char cmd_type,
/* send STOP */ writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat); - ReadWriteByte(); + ReadWriteByte(i2c); break;
default: - printf("i2c_transfer: bad call\n"); + debug("i2c_transfer: bad call\n"); result = I2C_NOK; break; }
- return (result); + return result; }
int i2c_probe(uchar chip) { + struct s3c24x0_i2c *i2c; uchar buf[1];
+ i2c = get_base_i2c(); buf[0] = 0;
/* @@ -360,16 +399,17 @@ int i2c_probe(uchar chip) * address was <ACK>ed (i.e. there was a chip at that address which * drove the data line low). */ - return i2c_transfer(I2C_READ, chip << 1, 0, 0, buf, 1) != I2C_OK; + return i2c_transfer(i2c, I2C_READ, chip << 1, 0, 0, buf, 1) != I2C_OK; }
int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) { + struct s3c24x0_i2c *i2c; uchar xaddr[4]; int ret;
if (alen > 4) { - printf("I2C read: addr len %d not supported\n", alen); + debug("I2C read: addr len %d not supported\n", alen); return 1; }
@@ -396,10 +436,11 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len) chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); #endif - if ((ret = - i2c_transfer(I2C_READ, chip << 1, &xaddr[4 - alen], alen, - buffer, len)) != 0) { - printf("I2c read: failed %d\n", ret); + i2c = get_base_i2c(); + ret = i2c_transfer(i2c, I2C_READ, chip << 1, &xaddr[4 - alen], alen, + buffer, len); + if (ret != 0) { + debug("I2c read: failed %d\n", ret); return 1; } return 0; @@ -407,10 +448,11 @@ int i2c_read(uchar chip, uint addr, int alen, uchar *buffer, int len)
int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) { + struct s3c24x0_i2c *i2c; uchar xaddr[4];
if (alen > 4) { - printf("I2C write: addr len %d not supported\n", alen); + debug("I2C write: addr len %d not supported\n", alen); return 1; }
@@ -436,8 +478,9 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) chip |= ((addr >> (alen * 8)) & CONFIG_SYS_I2C_EEPROM_ADDR_OVERFLOW); #endif + i2c = get_base_i2c(); return (i2c_transfer - (I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer, + (i2c, I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer, len) != 0); } #endif /* CONFIG_HARD_I2C */