[U-Boot] [PATCH 16/16] SPI: EXYNOS: Add FDT support to driver.

[Rajeshwari Birje]

Hi Minkyu Kang,

Thank you for comments.Will correct them.

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:
> > This patch adds FDT support to the SPI driver.
> >
> > Signed-off-by: Simon Glass <sjg at chromium.org>
> > Signed-off-by: Rajeshwari Shinde <rajeshwari.s at samsung.com>
> > Acked-by: Simon Glass <sjg at chromium.org>
> > ---
> > Changes in V1:
> >       -Rebased on latest u-boot-samsung
> >  drivers/spi/exynos_spi.c |   96
> +++++++++++++++++++++++++++++++++++++++++++---
> >  1 files changed, 90 insertions(+), 6 deletions(-)
> >
> > diff --git a/drivers/spi/exynos_spi.c b/drivers/spi/exynos_spi.c
> > index 3e6c18f..7ecc566 100644
> > --- a/drivers/spi/exynos_spi.c
> > +++ b/drivers/spi/exynos_spi.c
> > @@ -20,6 +20,7 @@
> >  #include <common.h>
> >  #include <malloc.h>
> >  #include <spi.h>
> > +#include <fdtdec.h>
> >  #include <asm/arch/clk.h>
> >  #include <asm/arch/clock.h>
> >  #include <asm/arch/cpu.h>
> > @@ -28,16 +29,20 @@
> >  #include <asm/arch-exynos/spi.h>
> >  #include <asm/io.h>
> >
> > +DECLARE_GLOBAL_DATA_PTR;
> > +
> >  /* Information about each SPI controller */
> >  struct spi_bus {
> >       enum periph_id periph_id;
> >       s32 frequency;          /* Default clock frequency, -1 for none */
> >       struct exynos_spi *regs;
> >       int inited;             /* 1 if this bus is ready for use */
> > +     int node;
> >  };
> >
> >  /* A list of spi buses that we know about */
> >  static struct spi_bus spi_bus[EXYNOS5_SPI_NUM_CONTROLLERS];
> > +static unsigned int bus_count;
> >
> >  struct exynos_spi_slave {
> >       struct spi_slave slave;
> > @@ -50,7 +55,7 @@ struct exynos_spi_slave {
> >
> >  static struct spi_bus *spi_get_bus(unsigned dev_index)
> >  {
> > -     if (dev_index < EXYNOS5_SPI_NUM_CONTROLLERS)
> > +     if (dev_index < bus_count)
> >               return &spi_bus[dev_index];
> >       debug("%s: invalid bus %d", __func__, dev_index);
> >
> > @@ -347,21 +352,100 @@ static inline struct exynos_spi *get_spi_base(int
> dev_index)
> >                                       (dev_index - 3);
> >  }
> >
> > +/*
> > + * Read the SPI config from the device tree node.
> > + *
> > + * @param blob  FDT blob to read from
> > + * @param node  Node offset to read from
> > + * @param bus   SPI bus structure to fill with information
> > + * @return 0 if ok, or -FDT_ERR_NOTFOUND if something was missing
> > + */
> > +static int spi_get_config(const void *blob, int node, struct spi_bus
> *bus)
> > +{
> > +     bus->node = node;
> > +     bus->regs = (struct exynos_spi *)fdtdec_get_addr(blob, node,
> "reg");
> > +     bus->periph_id = pinmux_decode_periph_id(blob, node);
>
> Please add blank line here.
>
> > +     if (bus->periph_id == PERIPH_ID_NONE) {
> > +             debug("%s: Invalid peripheral ID %d\n", __func__,
> > +                     bus->periph_id);
> > +             return -FDT_ERR_NOTFOUND;
> > +     }
> > +
> > +     /* Use 500KHz as a suitable default */
> > +     bus->frequency = fdtdec_get_int(blob, node, "spi-max-frequency",
> > +                                     500000);
> > +
> > +     return 0;
> > +}
> > +
>
> Please remove this blank line.
>
> > +
> > +/*
> > + * Process a list of nodes, adding them to our list of SPI ports.
> > + *
> > + * @param blob          fdt blob
> > + * @param node_list     list of nodes to process (any <=0 are ignored)
> > + * @param count         number of nodes to process
> > + * @param is_dvc        1 if these are DVC ports, 0 if standard I2C
> > + * @return 0 if ok, -1 on error
> > + */
> > +static int process_nodes(const void *blob, int node_list[], int count)
> > +{
> > +     int i;
> > +
> > +     /* build the i2c_controllers[] for each controller */
> > +     for (i = 0; i < count; i++) {
> > +             int node = node_list[i];
> > +             struct spi_bus *bus;
> > +
> > +             if (node <= 0)
> > +                     continue;
> > +
> > +             bus = &spi_bus[i];
> > +             if (spi_get_config(blob, node, bus)) {
> > +                     printf("exynos spi_init: failed to decode bus
> %d\n",
> > +                             i);
> > +                     return -1;
> > +             }
> > +
> > +             debug("spi: controller bus %d at %p, periph_id %d\n",
> > +                   i, bus->regs, bus->periph_id);
> > +             bus->inited = 1;
> > +             bus_count++;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> >  /* Sadly there is no error return from this function */
> >  void spi_init(void)
> >  {
> > -     int i;
> > +     int count;
> > +
> > +#ifdef CONFIG_OF_CONTROL
> > +     int node_list[EXYNOS5_SPI_NUM_CONTROLLERS];
> > +     const void *blob = gd->fdt_blob;
> > +
> > +     count = fdtdec_find_aliases_for_id(blob, "spi",
> > +                     COMPAT_SAMSUNG_EXYNOS_SPI, node_list,
> > +                     EXYNOS5_SPI_NUM_CONTROLLERS);
> > +     if (process_nodes(blob, node_list, count))
> > +             return;
> > +
> > +#else
> >       struct spi_bus *bus;
> >
> > -     for (i = 0; i < EXYNOS5_SPI_NUM_CONTROLLERS; i++) {
> > -             bus = &spi_bus[i];
> > -             bus->regs = get_spi_base(i);
> > -             bus->periph_id = PERIPH_ID_SPI0 + i;
> > +     for (count = 0; i < EXYNOS5_SPI_NUM_CONTROLLERS; i++) {
>
> i or count?
> Is it typo?
>
> > +             bus = &spi_bus[count];
> > +             bus->regs = get_spi_base(count);
> > +             bus->periph_id = PERIPH_ID_SPI0 + count;
> >
> >               /* Although Exynos5 supports upto 50Mhz speed,
> >                * we are setting it to 10Mhz for safe side
> >                */
> >               bus->frequency = 10000000;
> >               bus->inited = 1;
> > +             bus->node = 0;
> > +             bus_count = EXYNOS5_SPI_NUM_CONTROLLERS;
> >       }
> > +#endif
> >  }
> >
>
> --
> Thanks,
> Minkyu Kang.
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>



-- 
Regards,
Rajeshwari Shinde