On Thu, Apr 19, 2012 at 05:50:12PM +0200, Roland Stigge wrote:
> This patch adds device tree support to the pnx-i2c driver by using platform
> resources for memory region and irq and removing dependency on mach includes.
> 
> The following platforms are affected:
> 
> * PNX
> * LPC31xx (WIP)
> * LPC32xx
> 
> The patch is based on a patch by Jon Smirl, working on lpc31xx integration
> 
> Signed-off-by: Roland Stigge <[email protected]>
> Reviewed-by: Arnd Bergmann <[email protected]>
> 
> ---
> 
> Applies to v3.4-rc3 + already applied i2c-pnx.c patches from this series
> 
> NOTE: I separated out this patch from the first patch series of the LPC32xx
> device tree conversion because most of those patches are already applied to
> -next. This is the last patch of this first series, a precondition for the
> LPC32xx device tree switch.
> 
> Changes since v3:
> * Documentation/devicetree/bindings/i2c/pnx.txt:
>   - Documented interrupt-parent as required
>   - Documented slave-addr default in hex
> 
>  Documentation/devicetree/bindings/i2c/pnx.txt |   40 ++++++++++++++++
>  drivers/i2c/busses/i2c-pnx.c                  |   65 
> +++++++++++++++++++-------
>  include/linux/i2c-pnx.h                       |    1 
>  3 files changed, 89 insertions(+), 17 deletions(-)
> 
> --- /dev/null
> +++ linux-2.6/Documentation/devicetree/bindings/i2c/pnx.txt
> @@ -0,0 +1,40 @@
> +* NXP PNX I2C Controller
> +
> +Required properties:
> +
> + - reg: Offset and length of the register set for the device
> + - compatible: should be "nxp,pnx-i2c"
> + - interrupts: configure one interrupt line
> + - #address-cells: always 1 (for i2c addresses)
> + - #size-cells: always 0
> + - interrupt-parent: the phandle for the interrupt controller that
> +   services interrupts for this device.
> +
> +Optional properties:
> +
> + - clock-frequency: desired I2C bus clock frequency in Hz, Default: 100000 Hz
> + - pnx,timeout: I2C bus timeout in milliseconds, Default: 10 ms

I'd like to repeat my question to the devicetree folks here: Can we have
timeout generic? It doesn't make sense to me to have that per vendor
again and again. I searched devicetree.org and EPAPR but couldn't find a
hint.

> + - slave-addr: Address used by the controller, Hardware default: 0x6e
> +
> +Examples:
> +
> +     i2c1: i2c@400a0000 {
> +             compatible = "nxp,pnx-i2c";
> +             reg = <0x400a0000 0x100>;
> +             interrupt-parent = <&mic>;
> +             interrupts = <51 0>;
> +             #address-cells = <1>;
> +             #size-cells = <0>;
> +     };
> +
> +     i2c2: i2c@400a8000 {
> +             compatible = "nxp,pnx-i2c";
> +             reg = <0x400a8000 0x100>;
> +             interrupt-parent = <&mic>;
> +             interrupts = <50 0>;
> +             #address-cells = <1>;
> +             #size-cells = <0>;
> +             clock-frequency = <0x186a0>;
> +             pnx,timeout = <0x64>;

Did you change this, too? Timeouts are better readable in dec :)

> +             slave-addr = <0x11>;
> +     };
> --- linux-2.6.orig/drivers/i2c/busses/i2c-pnx.c
> +++ linux-2.6/drivers/i2c/busses/i2c-pnx.c
> @@ -23,10 +23,11 @@
>  #include <linux/err.h>
>  #include <linux/clk.h>
>  #include <linux/slab.h>
> +#include <linux/of_i2c.h>
>  
> -#define I2C_PNX_TIMEOUT              10 /* msec */
> -#define I2C_PNX_SPEED_KHZ    100
> -#define I2C_PNX_REGION_SIZE  0x100
> +#define I2C_PNX_TIMEOUT_DEFAULT              10 /* msec */
> +#define I2C_PNX_SPEED_KHZ_DEFAULT    100
> +#define I2C_PNX_REGION_SIZE          0x100
>  
>  enum {
>       mstatus_tdi = 0x00000001,
> @@ -74,8 +75,9 @@ enum {
>  #define I2C_REG_TXS(a)       ((a)->ioaddr + 0x28)    /* Tx slave FIFO (RO) */
>  #define I2C_REG_STFL(a)      ((a)->ioaddr + 0x2c)    /* Tx slave FIFO level 
> (RO) */
>  
> -static inline int wait_timeout(long timeout, struct i2c_pnx_algo_data *data)
> +static inline int wait_timeout(struct i2c_pnx_algo_data *data)
>  {
> +     long timeout = data->timeout;
>       while (timeout > 0 &&
>                       (ioread32(I2C_REG_STS(data)) & mstatus_active)) {
>               mdelay(1);
> @@ -84,8 +86,9 @@ static inline int wait_timeout(long time
>       return (timeout <= 0);
>  }
>  
> -static inline int wait_reset(long timeout, struct i2c_pnx_algo_data *data)
> +static inline int wait_reset(struct i2c_pnx_algo_data *data)
>  {
> +     long timeout = data->timeout;
>       while (timeout > 0 &&
>                       (ioread32(I2C_REG_CTL(data)) & mcntrl_reset)) {
>               mdelay(1);
> @@ -97,7 +100,7 @@ static inline int wait_reset(long timeou
>  static inline void i2c_pnx_arm_timer(struct i2c_pnx_algo_data *alg_data)
>  {
>       struct timer_list *timer = &alg_data->mif.timer;
> -     unsigned long expires = msecs_to_jiffies(I2C_PNX_TIMEOUT);
> +     unsigned long expires = msecs_to_jiffies(alg_data->timeout);
>  
>       if (expires <= 1)
>               expires = 2;
> @@ -135,7 +138,7 @@ static int i2c_pnx_start(unsigned char s
>       }
>  
>       /* First, make sure bus is idle */
> -     if (wait_timeout(I2C_PNX_TIMEOUT, alg_data)) {
> +     if (wait_timeout(alg_data)) {
>               /* Somebody else is monopolizing the bus */
>               dev_err(&alg_data->adapter.dev,
>                       "%s: Bus busy. Slave addr = %02x, cntrl = %x, stat = 
> %x\n",
> @@ -228,7 +231,7 @@ static int i2c_pnx_master_xmit(struct i2
>               if (alg_data->mif.len == 0) {
>                       if (alg_data->last) {
>                               /* Wait until the STOP is seen. */
> -                             if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
> +                             if (wait_timeout(alg_data))
>                                       dev_err(&alg_data->adapter.dev,
>                                               "The bus is still active after 
> timeout\n");
>                       }
> @@ -326,7 +329,7 @@ static int i2c_pnx_master_rcv(struct i2c
>               if (alg_data->mif.len == 0) {
>                       if (alg_data->last)
>                               /* Wait until the STOP is seen. */
> -                             if (wait_timeout(I2C_PNX_TIMEOUT, alg_data))
> +                             if (wait_timeout(alg_data))
>                                       dev_err(&alg_data->adapter.dev,
>                                               "The bus is still active after 
> timeout\n");
>  
> @@ -442,7 +445,7 @@ static void i2c_pnx_timeout(unsigned lon
>  
>       ctl |= mcntrl_reset;
>       iowrite32(ctl, I2C_REG_CTL(alg_data));
> -     wait_reset(I2C_PNX_TIMEOUT, alg_data);
> +     wait_reset(alg_data);
>       alg_data->mif.ret = -EIO;
>       complete(&alg_data->mif.complete);
>  }
> @@ -457,18 +460,18 @@ static inline void bus_reset_if_active(s
>                       alg_data->adapter.name);
>               iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
>                         I2C_REG_CTL(alg_data));
> -             wait_reset(I2C_PNX_TIMEOUT, alg_data);
> +             wait_reset(alg_data);
>       } else if (!(stat & mstatus_rfe) || !(stat & mstatus_tfe)) {
>               /* If there is data in the fifo's after transfer,
>                * flush fifo's by reset.
>                */
>               iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
>                         I2C_REG_CTL(alg_data));
> -             wait_reset(I2C_PNX_TIMEOUT, alg_data);
> +             wait_reset(alg_data);
>       } else if (stat & mstatus_nai) {
>               iowrite32(ioread32(I2C_REG_CTL(alg_data)) | mcntrl_reset,
>                         I2C_REG_CTL(alg_data));
> -             wait_reset(I2C_PNX_TIMEOUT, alg_data);
> +             wait_reset(alg_data);
>       }
>  }
>  
> @@ -612,6 +615,8 @@ static int __devinit i2c_pnx_probe(struc
>       struct i2c_pnx_algo_data *alg_data;
>       unsigned long freq;
>       struct resource *res;
> +     u32 speed = I2C_PNX_SPEED_KHZ_DEFAULT * 1000;
> +     u32 slave_addr = ~0;
>  
>       alg_data = kzalloc(sizeof(*alg_data), GFP_KERNEL);
>       if (!alg_data) {
> @@ -626,6 +631,18 @@ static int __devinit i2c_pnx_probe(struc
>       alg_data->adapter.algo_data = alg_data;
>       alg_data->adapter.nr = pdev->id;
>  
> +     alg_data->timeout = I2C_PNX_TIMEOUT_DEFAULT;
> +#ifdef CONFIG_OF
> +     alg_data->adapter.dev.of_node = of_node_get(pdev->dev.of_node);
> +     if (pdev->dev.of_node) {
> +             of_property_read_u32(pdev->dev.of_node, "pnx,timeout",
> +                                  &alg_data->timeout);
> +             of_property_read_u32(pdev->dev.of_node, "clock-frequency",
> +                                  &speed);
> +             of_property_read_u32(pdev->dev.of_node, "slave-addr",
> +                                  &slave_addr);
> +     }
> +#endif
>       alg_data->clk = clk_get(&pdev->dev, NULL);
>       if (IS_ERR(alg_data->clk)) {
>               ret = PTR_ERR(alg_data->clk);
> @@ -651,7 +668,7 @@ static int __devinit i2c_pnx_probe(struc
>               dev_err(&pdev->dev,
>                      "I/O region 0x%08x for I2C already in use.\n",
>                      res->start);
> -             ret = -ENODEV;
> +             ret = -ENOMEM;
>               goto out_clkget;
>       }
>  
> @@ -667,6 +684,9 @@ static int __devinit i2c_pnx_probe(struc
>       if (ret)
>               goto out_unmap;
>  
> +     if (slave_addr != ~0)
> +             iowrite32(slave_addr, I2C_REG_ADR(alg_data));
> +
>       freq = clk_get_rate(alg_data->clk);
>  
>       /*
> @@ -680,14 +700,14 @@ static int __devinit i2c_pnx_probe(struc
>        * the deglitching filter length.
>        */
>  
> -     tmp = ((freq / 1000) / I2C_PNX_SPEED_KHZ) / 2 - 2;
> +     tmp = (freq / speed) / 2 - 2;
>       if (tmp > 0x3FF)
>               tmp = 0x3FF;
>       iowrite32(tmp, I2C_REG_CKH(alg_data));
>       iowrite32(tmp, I2C_REG_CKL(alg_data));
>  
>       iowrite32(mcntrl_reset, I2C_REG_CTL(alg_data));
> -     if (wait_reset(I2C_PNX_TIMEOUT, alg_data)) {
> +     if (wait_reset(alg_data)) {
>               ret = -ENODEV;
>               goto out_clock;
>       }
> @@ -699,7 +719,7 @@ static int __devinit i2c_pnx_probe(struc
>               goto out_irq;
>       }
>       ret = request_irq(alg_data->irq, i2c_pnx_interrupt,
> -                     0, pdev->name, alg_data);
> +                       0, pdev->name, alg_data);
>       if (ret)
>               goto out_clock;
>  
> @@ -710,6 +730,8 @@ static int __devinit i2c_pnx_probe(struc
>               goto out_irq;
>       }
>  
> +     of_i2c_register_devices(&alg_data->adapter);
> +
>       dev_dbg(&pdev->dev, "%s: Master at %#8x, irq %d.\n",
>               alg_data->adapter.name, res->start, alg_data->irq);
>  
> @@ -748,10 +770,19 @@ static int __devexit i2c_pnx_remove(stru
>       return 0;
>  }
>  
> +#ifdef CONFIG_OF
> +static const struct of_device_id i2c_pnx_of_match[] = {
> +     { .compatible = "nxp,pnx-i2c" },
> +     { },
> +};
> +MODULE_DEVICE_TABLE(of, i2c_pnx_of_match);
> +#endif
> +
>  static struct platform_driver i2c_pnx_driver = {
>       .driver = {
>               .name = "pnx-i2c",
>               .owner = THIS_MODULE,
> +             .of_match_table = of_match_ptr(i2c_pnx_of_match),
>       },
>       .probe = i2c_pnx_probe,
>       .remove = __devexit_p(i2c_pnx_remove),
> --- linux-2.6.orig/include/linux/i2c-pnx.h
> +++ linux-2.6/include/linux/i2c-pnx.h
> @@ -32,6 +32,7 @@ struct i2c_pnx_algo_data {
>       struct i2c_adapter      adapter;
>       phys_addr_t             base;
>       int                     irq;
> +     u32                     timeout;
>  };
>  
>  #endif /* __I2C_PNX_H__ */

-- 
Pengutronix e.K.                           | Wolfram Sang                |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |

Attachment: signature.asc
Description: Digital signature

Reply via email to