Hi Rajeshwari,
On Wed, Nov 7, 2012 at 9:30 PM, Rajeshwari Shinde rajeshwari.s@samsung.com wrote:
Functions added to get the I2C bus number and reset I2C bus using FDT node.
Signed-off-by: Simon Glass sjg@chromium.org Signed-off-by: Rajeshwari Shinde rajeshwari.s@samsung.com
drivers/i2c/s3c24x0_i2c.c | 89 ++++++++++++++++++++++++++++++++++++++++++++- drivers/i2c/s3c24x0_i2c.h | 7 ++++ include/i2c.h | 28 ++++++++++++++ 3 files changed, 123 insertions(+), 1 deletions(-)
diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c index 9bc4c7f..952f76c 100644 --- a/drivers/i2c/s3c24x0_i2c.c +++ b/drivers/i2c/s3c24x0_i2c.c @@ -27,6 +27,7 @@ */
#include <common.h> +#include <fdtdec.h> #ifdef CONFIG_EXYNOS5 #include <asm/arch/clk.h> #include <asm/arch/cpu.h> @@ -60,7 +61,14 @@ #define I2C_TIMEOUT 1 /* 1 second */
-static unsigned int g_current_bus; /* Stores Current I2C Bus */ +/*
- For SPL boot some boards need i2c before SDRAM is initialised so force
- variables to live in SRAM
- */
+static unsigned int g_current_bus __attribute__((section(".data"))); +static struct s3c24x0_i2c_bus i2c_bus[CONFIG_MAX_I2C_NUM]
__attribute__((section(".data")));+static int i2c_busses __attribute__((section(".data")));
#ifndef CONFIG_EXYNOS5 static int GetI2CSDA(void) @@ -507,4 +515,83 @@ int i2c_write(uchar chip, uint addr, int alen, uchar *buffer, int len) (i2c, I2C_WRITE, chip << 1, &xaddr[4 - alen], alen, buffer, len) != 0); }
+#ifdef CONFIG_OF_CONTROL +unsigned int i2c_fdt_bus_values(const void *blob) +{
int node_list[CONFIG_MAX_I2C_NUM];int count, i;count = fdtdec_find_aliases_for_id(blob, "i2c",COMPAT_SAMSUNG_S3C2440_I2C, node_list,CONFIG_MAX_I2C_NUM);for (i = 0; i < count; i++) {struct s3c24x0_i2c_bus *bus;int node = node_list[i];if (node < 0)continue;bus = &i2c_bus[i];bus->regs = (struct s3c24x0_i2c *)fdtdec_get_addr(blob, node, "reg");bus->node = node;bus->bus_num = i2c_busses++;}return count;+}
This seems to be the init function for i2c, so how about calling it board_i2c_init() or similar. I don't think you need to return the count of i2c ports - you can just use CONFIG_MAX_I2C_NUM anywhere that it is needed.
+static struct s3c24x0_i2c_bus *get_bus(int bus_idx)
should probably be unsigned so that you don't need to check < 0
+{
if (bus_idx < i2c_busses)return &i2c_bus[bus_idx];debug("Undefined bus: %d\n", bus_idx);return NULL;+}
+int i2c_get_bus_num_fdt(const void *blob, int node) +{
enum fdt_compat_id compat;fdt_addr_t reg;int i;compat = fdtdec_lookup(blob, node);if (compat != COMPAT_SAMSUNG_S3C2440_I2C) {debug("%s: Not a supported I2C node\n", __func__);return -1;}reg = fdtdec_get_addr(blob, node, "reg");for (i = 0; i < i2c_busses; i++) {if (reg == (fdt_addr_t)(uintptr_t)i2c_bus[i].regs)return i;}
This seems painful. You already have a table of node versus bus number, created in the function above, so why not just look in that?
debug("%s: Can't find any matched I2C bus\n", __func__);return -1;+}
+int i2c_reset_port_fdt(const void *blob, int node) +{
struct s3c24x0_i2c_bus *i2c;int bus;bus = i2c_get_bus_num_fdt(blob, node);if (bus < 0) {debug("could not get bus for node %d\n", node);return -1;}i2c = get_bus(bus);if (!i2c) {debug("get_bus() failed for node node %d\n", node);return -1;}i2c_ch_init(i2c->regs, CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);return 0;+} +#endif
#endif /* CONFIG_HARD_I2C */ diff --git a/drivers/i2c/s3c24x0_i2c.h b/drivers/i2c/s3c24x0_i2c.h index 2dd4b06..bdd5514 100644 --- a/drivers/i2c/s3c24x0_i2c.h +++ b/drivers/i2c/s3c24x0_i2c.h @@ -30,4 +30,11 @@ struct s3c24x0_i2c { u32 iicds; u32 iiclc; };
+struct s3c24x0_i2c_bus {
int node; /* device tree node */int bus_num; /* i2c bus number */struct s3c24x0_i2c *regs;+};
#endif /* _S3C24X0_I2C_H */ diff --git a/include/i2c.h b/include/i2c.h index 16f099d..52be093 100644 --- a/include/i2c.h +++ b/include/i2c.h @@ -262,4 +262,32 @@ extern int get_multi_scl_pin(void); extern int get_multi_sda_pin(void); extern int multi_i2c_init(void); #endif
+#ifdef CONFIG_OF_CONTROL
I think you can omit this line - it doesn't hurt to have unused prototypes. We will get a link error if someone does something silly.
+/**
- Get FDT values for i2c bus.
- @param blob Device tree blbo
- @return the number of I2C bus
- */
+unsigned int i2c_fdt_bus_values(const void *blob);
+/**
- Find the I2C bus number by given a FDT I2C node.
- @param blob Device tree blbo
- @param node FDT I2C node to find
- @return the number of I2C bus (zero based), or -1 on error
- */
+int i2c_get_bus_num_fdt(const void *blob, int node);
+/**
- Reset the I2C bus represented by the given a FDT I2C node.
- @param blob Device tree blbo
- @param node FDT I2C node to find
- @return 0 if port was reset, -1 if not found
- */
+int i2c_reset_port_fdt(const void *blob, int node); +#endif
#endif /* _I2C_H_ */
1.7.4.4
Regards, Simon