
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 - I2C init for Exynos5 is made as different function. - Channel initialisation is moved to a commom funation as it is required by both the i2c_init. - Separate functions written to get I2C base address, peripheral id for pinmux support. - Hardcoding for I2CCON_ACKGEN removed. - Replaced printf with debug. - Checkpatch issues resolved.
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. drivers/i2c/s3c24x0_i2c.c | 243 +++++++++++++++++++++++++++++++-------------- drivers/i2c/s3c24x0_i2c.h | 3 + 2 files changed, 172 insertions(+), 74 deletions(-)
diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c index ba6f39b..156b5a4 100644 --- a/drivers/i2c/s3c24x0_i2c.c +++ b/drivers/i2c/s3c24x0_i2c.c @@ -27,10 +27,17 @@ */
#include <common.h> +#ifdef CONFIG_EXYNOS5 +#include <asm/arch/clk.h> +#include <asm/arch/cpu.h> +#include <asm/arch/gpio.h> +#include <asm/arch/pinmux.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 +52,7 @@
#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 +61,48 @@
#define I2C_TIMEOUT 1 /* 1 second */
+#ifdef CONFIG_EXYNOS5 +static unsigned int g_current_bus; /* Stores Current I2C Bus */ + +/* We should not rely on any particular ordering of these IDs */ +static enum periph_id periph_for_dev[] = { + PERIPH_ID_I2C0, + PERIPH_ID_I2C1, + PERIPH_ID_I2C2, + PERIPH_ID_I2C3, + PERIPH_ID_I2C4, + PERIPH_ID_I2C5, + PERIPH_ID_I2C6, + PERIPH_ID_I2C7, +}; + +static enum periph_id i2c_get_periph_id(unsigned dev_index) +{ + if (dev_index < ARRAY_SIZE(periph_for_dev)) + return periph_for_dev[dev_index]; + + debug("%s: invalid bus %d", __func__, dev_index); + + return PERIPH_ID_NONE; +} + +static struct s3c24x0_i2c *get_base_i2c(int bus_idx) +{ +#ifdef CONFIG_EXYNOS5 + struct s3c24x0_i2c *i2c = (struct s3c24x0_i2c *)samsung_get_base_i2c(); + return &i2c[bus_idx]; +#else + return s3c24x0_get_base_i2c(); +#endif + +} + +static inline struct exynos5_gpio_part1 *exynos_get_base_gpio1(void) +{ + return (struct exynos5_gpio_part1 *)(EXYNOS5_GPIO_PART1_BASE); +} + +#else static int GetI2CSDA(void) { struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); @@ -77,16 +127,17 @@ 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; @@ -98,25 +149,79 @@ 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 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); +} + +static void i2c_bus_init(struct s3c24x0_i2c *i2c, unsigned int bus) +{ + int periph_id = i2c_get_periph_id(bus); + + exynos_pinmux_config(periph_id, 0); + + i2c_ch_init(i2c, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE); +} + +#ifdef CONFIG_EXYNOS5 +void i2c_init(int speed, int slaveadd) +{ + struct s3c24x0_i2c *i2c; + struct exynos5_gpio_part1 *gpio; + int i; + + /* By default i2c channel 0 is the current bus */ + g_current_bus = I2C0; + + i2c = get_base_i2c(g_current_bus); + + i2c_bus_init(i2c, g_current_bus); + + /* 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--; + } +} + +#else void i2c_init(int speed, int slaveadd) { - struct s3c24x0_i2c *i2c = s3c24x0_get_base_i2c(); + struct s3c24x0_i2c *i2c = get_base_i2c(); struct s3c24x0_gpio *gpio = s3c24x0_get_base_gpio(); - ulong freq, pres = 16, div; int i;
/* wait for some time to give previous transfer a chance to finish */ @@ -171,27 +276,9 @@ 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
/* * cmd_type is 0 for write, 1 for read. @@ -200,19 +287,19 @@ 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 +313,7 @@ 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 +325,16 @@ 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 +344,19 @@ 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 +366,13 @@ 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 +380,17 @@ 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 +404,18 @@ 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 +426,24 @@ 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(g_current_bus); buf[0] = 0;
/* @@ -360,16 +451,17 @@ 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 +488,11 @@ 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(g_current_bus); + 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 +500,11 @@ 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 +530,9 @@ 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(g_current_bus); 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 */ diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h index d357a0a..57aafb1 100644 --- a/drivers/i2c/s3c24x0_i2c.h +++ b/drivers/i2c/s3c24x0_i2c.h @@ -23,6 +23,9 @@ #ifndef _S3C24X0_I2C_H #define _S3C24X0_I2C_H
+/* I2C channels exynos5 has 8 i2c channel */ +#define I2C0 0 + struct s3c24x0_i2c { u32 iiccon; u32 iicstat;