[U-Boot] [PATCH 5/6] i2c: designware_i2c: Add DM support

[Bin Meng <bmeng.cn@gmail.com>]

Hi Stefan,

On Fri, Mar 18, 2016 at 3:54 PM, Stefan Roese <sr@denx.de> wrote:
> This patch adds DM support to the designware I2C driver. It currently
> supports DM and the legacy I2C support. The legacy support should be
> removed, once all platforms using it have DM enabled.
>
> Signed-off-by: Stefan Roese <sr@denx.de>
> Cc: Simon Glass <sjg@chromium.org>
> Cc: Bin Meng <bmeng.cn@gmail.com>
> Cc: Marek Vasut <marex@denx.de>
> Cc: Heiko Schocher <hs@denx.de>
> ---
>  drivers/i2c/designware_i2c.c | 149 ++++++++++++++++++++++++++++++++++++-------
>  1 file changed, 126 insertions(+), 23 deletions(-)
>
> diff --git a/drivers/i2c/designware_i2c.c b/drivers/i2c/designware_i2c.c
> index e51e6de..4e5340d 100644
> --- a/drivers/i2c/designware_i2c.c
> +++ b/drivers/i2c/designware_i2c.c
> @@ -6,10 +6,15 @@
>   */
>
>  #include <common.h>
> +#include <dm.h>
>  #include <i2c.h>
>  #include <asm/io.h>
>  #include "designware_i2c.h"
>
> +struct dw_i2c {
> +       struct i2c_regs *regs;
> +};
> +
>  static void dw_i2c_enable(struct i2c_regs *i2c_base, bool enable)
>  {
>         int timeout = 100;
> @@ -293,6 +298,36 @@ static int __dw_i2c_write(struct i2c_regs *i2c_base, u8 dev, uint addr,
>         return i2c_xfer_finish(i2c_base);
>  }
>
> +/*
> + * i2c_init - Init function

__dw_i2c_init

> + * @speed:     required i2c speed
> + * @slaveaddr: slave address for the device
> + *
> + * Initialization function.
> + */
> +static void __dw_i2c_init(struct i2c_regs *i2c_base, int speed, int slaveaddr)
> +{
> +       /* Disable i2c */
> +       dw_i2c_enable(i2c_base, 0);
> +
> +       writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_base->ic_con);
> +       writel(IC_RX_TL, &i2c_base->ic_rx_tl);
> +       writel(IC_TX_TL, &i2c_base->ic_tx_tl);
> +       writel(IC_STOP_DET, &i2c_base->ic_intr_mask);
> +#ifndef CONFIG_DM_I2C
> +       __dw_i2c_set_bus_speed(i2c_base, speed);
> +       writel(slaveaddr, &i2c_base->ic_sar);
> +#endif
> +
> +       /* Enable i2c */
> +       dw_i2c_enable(i2c_base, 1);
> +}
> +
> +#ifndef CONFIG_DM_I2C
> +/*
> + * The legacy I2C functions. These need to get removed once
> + * all users of this driver are converted to DM.
> + */
>  static struct i2c_regs *i2c_get_base(struct i2c_adapter *adap)
>  {
>         switch (adap->hwadapnr) {
> @@ -324,30 +359,9 @@ static unsigned int dw_i2c_set_bus_speed(struct i2c_adapter *adap,
>         return __dw_i2c_set_bus_speed(i2c_get_base(adap), speed);
>  }
>
> -/*
> - * i2c_init - Init function
> - * @speed:     required i2c speed
> - * @slaveaddr: slave address for the device
> - *
> - * Initialization function.
> - */
> -static void dw_i2c_init(struct i2c_adapter *adap, int speed,
> -                       int slaveaddr)
> +static void dw_i2c_init(struct i2c_adapter *adap, int speed, int slaveaddr)
>  {
> -       struct i2c_regs *i2c_base = i2c_get_base(adap);
> -
> -       /* Disable i2c */
> -       dw_i2c_enable(i2c_base, 0);
> -
> -       writel((IC_CON_SD | IC_CON_SPD_FS | IC_CON_MM), &i2c_base->ic_con);
> -       writel(IC_RX_TL, &i2c_base->ic_rx_tl);
> -       writel(IC_TX_TL, &i2c_base->ic_tx_tl);
> -       dw_i2c_set_bus_speed(adap, speed);
> -       writel(IC_STOP_DET, &i2c_base->ic_intr_mask);
> -       writel(slaveaddr, &i2c_base->ic_sar);
> -
> -       /* Enable i2c */
> -       dw_i2c_enable(i2c_base, 1);
> +       __dw_i2c_init(i2c_get_base(adap), speed, slaveaddr);
>  }
>
>  static int dw_i2c_read(struct i2c_adapter *adap, u8 dev, uint addr,
> @@ -402,3 +416,92 @@ U_BOOT_I2C_ADAP_COMPLETE(dw_3, dw_i2c_init, dw_i2c_probe, dw_i2c_read,
>                          dw_i2c_write, dw_i2c_set_bus_speed,
>                          CONFIG_SYS_I2C_SPEED3, CONFIG_SYS_I2C_SLAVE3, 3)
>  #endif
> +
> +#else /* CONFIG_DM_I2C */
> +/*
> + * The DM I2C functions
> + */

nits: single line comment format

> +
> +static int designware_i2c_xfer(struct udevice *bus, struct i2c_msg *msg,
> +                              int nmsgs)
> +{
> +       struct dw_i2c *i2c = dev_get_priv(bus);
> +       int ret;
> +
> +       debug("i2c_xfer: %d messages\n", nmsgs);
> +       for (; nmsgs > 0; nmsgs--, msg++) {
> +               debug("i2c_xfer: chip=0x%x, len=0x%x\n", msg->addr, msg->len);
> +               if (msg->flags & I2C_M_RD) {
> +                       ret = __dw_i2c_read(i2c->regs, msg->addr, 0, 0,
> +                                           msg->buf, msg->len);
> +               } else {
> +                       ret = __dw_i2c_write(i2c->regs, msg->addr, 0, 0,
> +                                            msg->buf, msg->len);
> +               }
> +               if (ret) {
> +                       debug("i2c_write: error sending\n");
> +                       return -EREMOTEIO;
> +               }
> +       }
> +
> +       return 0;
> +}
> +
> +static int designware_i2c_set_bus_speed(struct udevice *bus, unsigned int speed)
> +{
> +       struct dw_i2c *i2c = dev_get_priv(bus);
> +
> +       return __dw_i2c_set_bus_speed(i2c->regs, speed);
> +}
> +
> +static int designware_i2c_probe_chip(struct udevice *bus, uint chip_addr,
> +                                    uint chip_flags)
> +{
> +       struct dw_i2c *i2c = dev_get_priv(bus);
> +       struct i2c_regs *i2c_base = i2c->regs;
> +       u32 tmp;
> +       int ret;
> +
> +       /*
> +        * Try to read the first location of the chip.
> +        */

nits: single line comment format

> +       ret = __dw_i2c_read(i2c_base, chip_addr, 0, 1, (uchar *)&tmp, 1);
> +       if (ret)
> +               __dw_i2c_init(i2c_base, 0, 0);
> +
> +       return ret;
> +}
> +
> +static int designware_i2c_probe(struct udevice *bus)
> +{
> +       struct dw_i2c *priv = dev_get_priv(bus);
> +
> +       /* Save base address from device-tree */
> +       priv->regs = (struct i2c_regs *)dev_get_addr(bus);
> +
> +       __dw_i2c_init(priv->regs, 0, 0);
> +
> +       return 0;
> +}
> +
> +static const struct dm_i2c_ops designware_i2c_ops = {
> +       .xfer           = designware_i2c_xfer,
> +       .probe_chip     = designware_i2c_probe_chip,
> +       .set_bus_speed  = designware_i2c_set_bus_speed,
> +};
> +
> +static const struct udevice_id designware_i2c_ids[] = {
> +       { .compatible = "snps,designware-i2c" },
> +       { }
> +};
> +
> +U_BOOT_DRIVER(i2c_designware) = {
> +       .name   = "i2c_designware",
> +       .id     = UCLASS_I2C,
> +       .of_match = designware_i2c_ids,
> +       .probe  = designware_i2c_probe,
> +       .priv_auto_alloc_size = sizeof(struct dw_i2c),
> +       .ops    = &designware_i2c_ops,
> +};
> +
> +#endif /* CONFIG_DM_I2C */
> --

Other than that,
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

Regards,
Bin