[U-Boot] [PATCH 05/16] I2C: Driver changes for FDT support
Minkyu Kang
promsoft at gmail.com
Wed Dec 26 15:00:34 CET 2012
On 26 December 2012 21:33, Rajeshwari Birje <rajeshwari.birje at gmail.com>wrote:
> Hi Minkyu Kang,
>
> On Wed, Dec 26, 2012 at 5:24 PM, Minkyu Kang <mk7.kang at samsung.com> wrote:
>
> > Dear Rajeshwari Shinde,
> >
> > On 14/12/12 20:56, Rajeshwari Shinde wrote:
> > > Functions added to get the I2C bus number and reset I2C bus using
> > > FDT node.
> > >
> > > Signed-off-by: Rajeshwari Shinde <rajeshwari.s at samsung.com>
> > > Acked-by: Simon Glass <sjg at chromium.org>
> > > Acked-by: Heiko Schocher <hs at denx.de>
> > > ---
> > > Changes in V1:
> > > -Rebased on latest u-boot-samsung
> > > drivers/i2c/s3c24x0_i2c.c | 83
> > ++++++++++++++++++++++++++++++++++++++++++++-
> > > drivers/i2c/s3c24x0_i2c.h | 8 ++++
> > > include/i2c.h | 26 ++++++++++++++
> > > 3 files changed, 116 insertions(+), 1 deletions(-)
> > >
> > > diff --git a/drivers/i2c/s3c24x0_i2c.c b/drivers/i2c/s3c24x0_i2c.c
> > > index 9bc4c7f..94a093e 100644
> > > --- a/drivers/i2c/s3c24x0_i2c.c
> > > +++ b/drivers/i2c/s3c24x0_i2c.c
> > > @@ -27,9 +27,11 @@
> > > */
> > >
> > > #include <common.h>
> > > +#include <fdtdec.h>
> > > #ifdef CONFIG_EXYNOS5
> > > #include <asm/arch/clk.h>
> > > #include <asm/arch/cpu.h>
> > > +#include <asm/arch/pinmux.h>
> > > #else
> > > #include <asm/arch/s3c24x0_cpu.h>
> > > #endif
> > > @@ -60,7 +62,14 @@
> > > #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 +516,76 @@ 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
> > > +void board_i2c_init(const void *blob)
> > > +{
> > > +
> >
> > please remove this blank line.
> >
> > > + 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);
> >
> > need blank line here.
> >
> > > + for (i = 0; i < count; i++) {
> > > + struct s3c24x0_i2c_bus *bus;
> > > + int node = node_list[i];
> >
> > How handle if the value of count is bigger than CONFIG_MAX_I2C_NUM?
> >
> CONFIG_MAX_I2C_NUM is maximum number of I2C lines supported.
> if count bigger than CONFIG_MAX_I2C_NUM then it is error.
> So you want me to add a check here?
>
It seems to check at fdtdec_find_aliases_fo_id function.
Then OK, enough.
>
> >
> > > +
> > > + if (node <= 0)
> > > + continue;
> > > + bus = &i2c_bus[i];
> > > + bus->regs = (struct s3c24x0_i2c *)
> > > + fdtdec_get_addr(blob, node, "reg");
> > > + bus->id = pinmux_decode_periph_id(blob, node);
> > > + bus->node = node;
> > > + bus->bus_num = i2c_busses++;
> > > + exynos_pinmux_config(bus->id, 0);
> > > + }
> > > +
> >
> > please remove this blank line.
> >
> > > +}
> > > +
> > > +static struct s3c24x0_i2c_bus *get_bus(unsigned int bus_idx)
> > > +{
> > > + if (bus_idx < i2c_busses)
> > > + return &i2c_bus[bus_idx];
> >
> > need blank line here.
> >
> > > + debug("Undefined bus: %d\n", bus_idx);
> > > + return NULL;
> > > +}
> > > +
> > > +int i2c_get_bus_num_fdt(int node)
> > > +{
> > > + int i;
> > > +
> > > + for (i = 0; i < i2c_busses; i++) {
> > > + if (node == i2c_bus[i].node)
> > > + return i;
> > > + }
> > > +
> > > + 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;
> > > +
> >
> > Please remove this blank line.
> >
> > > + int bus;
> > > +
> > > + bus = i2c_get_bus_num_fdt(node);
> > > + if (bus < 0) {
> > > + debug("could not get bus for node %d\n", node);
> > > + return -1;
> > > + }
> >
> > need blank line here.
> >
> > > + 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..1243bf1 100644
> > > --- a/drivers/i2c/s3c24x0_i2c.h
> > > +++ b/drivers/i2c/s3c24x0_i2c.h
> > > @@ -30,4 +30,12 @@ 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;
> > > + enum periph_id id;
> > > +};
> > > +
> > > #endif /* _S3C24X0_I2C_H */
> > > diff --git a/include/i2c.h b/include/i2c.h
> > > index 16f099d..c60d075 100644
> > > --- a/include/i2c.h
> > > +++ b/include/i2c.h
> > > @@ -262,4 +262,30 @@ extern int get_multi_scl_pin(void);
> > > extern int get_multi_sda_pin(void);
> > > extern int multi_i2c_init(void);
> > > #endif
> > > +
> > > +/**
> > > + * Get FDT values for i2c bus.
> > > + *
> > > + * @param blob Device tree blbo
> > > + * @return the number of I2C bus
> > > + */
> > > +void board_i2c_init(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(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 /* _I2C_H_ */
> > >
> >
> > --
> > Thanks,
> > Minkyu Kang.
> > _______________________________________________
> > U-Boot mailing list
> > U-Boot at lists.denx.de
> > http://lists.denx.de/mailman/listinfo/u-boot
> >
>
>
>
> --
> Regards,
> Rajeshwari Shinde
>
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot
>
>
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