arch/arm/mach-s5p6442/dev-spi.c

   1 /* linux/arch/arm/mach-s5p6442/dev-spi.c
   2  *
   3  * Copyright (C) 2010 Samsung Electronics Co. Ltd.
   4  *      Jaswinder Singh <jassi.brar@samsung.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  */
  10
  11 #include <linux/platform_device.h>
  12 #include <linux/dma-mapping.h>
  13
  14 #include <mach/dma.h>
  15 #include <mach/map.h>
  16 #include <mach/irqs.h>
  17 #include <mach/gpio.h>
  18 #include <mach/spi-clocks.h>
  19
  20 #include <plat/s3c64xx-spi.h>
  21 #include <plat/gpio-cfg.h>
  22
  23 static char *spi_src_clks[] = {
  24         [S5P6442_SPI_SRCCLK_PCLK] = "pclk",
  25         [S5P6442_SPI_SRCCLK_SCLK] = "spi_epll",
  26 };
  27
  28 /* SPI Controller platform_devices */
  29
  30 /* Since we emulate multi-cs capability, we do not touch the CS.
  31  * The emulated CS is toggled by board specific mechanism, as it can
  32  * be either some immediate GPIO or some signal out of some other
  33  * chip in between ... or some yet another way.
  34  * We simply do not assume anything about CS.
  35  */
  36 static int s5p6442_spi_cfg_gpio(struct platform_device *pdev)
  37 {
  38         switch (pdev->id) {
  39         case 0:
  40                 s3c_gpio_cfgpin(S5P6442_GPB(0), S3C_GPIO_SFN(2));
  41                 s3c_gpio_cfgpin(S5P6442_GPB(2), S3C_GPIO_SFN(2));
  42                 s3c_gpio_cfgpin(S5P6442_GPB(3), S3C_GPIO_SFN(2));
  43                 s3c_gpio_setpull(S5P6442_GPB(0), S3C_GPIO_PULL_UP);
  44                 s3c_gpio_setpull(S5P6442_GPB(2), S3C_GPIO_PULL_UP);
  45                 s3c_gpio_setpull(S5P6442_GPB(3), S3C_GPIO_PULL_UP);
  46                 break;
  47
  48         default:
  49                 dev_err(&pdev->dev, "Invalid SPI Controller number!");
  50                 return -EINVAL;
  51         }
  52
  53         return 0;
  54 }
  55
  56 static struct resource s5p6442_spi0_resource[] = {
  57         [0] = {
  58                 .start = S5P6442_PA_SPI,
  59                 .end   = S5P6442_PA_SPI + 0x100 - 1,
  60                 .flags = IORESOURCE_MEM,
  61         },
  62         [1] = {
  63                 .start = DMACH_SPI0_TX,
  64                 .end   = DMACH_SPI0_TX,
  65                 .flags = IORESOURCE_DMA,
  66         },
  67         [2] = {
  68                 .start = DMACH_SPI0_RX,
  69                 .end   = DMACH_SPI0_RX,
  70                 .flags = IORESOURCE_DMA,
  71         },
  72         [3] = {
  73                 .start = IRQ_SPI0,
  74                 .end   = IRQ_SPI0,
  75                 .flags = IORESOURCE_IRQ,
  76         },
  77 };
  78
  79 static struct s3c64xx_spi_info s5p6442_spi0_pdata = {
  80         .cfg_gpio = s5p6442_spi_cfg_gpio,
  81         .fifo_lvl_mask = 0x1ff,
  82         .rx_lvl_offset = 15,
  83 };
  84
  85 static u64 spi_dmamask = DMA_BIT_MASK(32);
  86
  87 struct platform_device s5p6442_device_spi = {
  88         .name             = "s3c64xx-spi",
  89         .id               = 0,
  90         .num_resources    = ARRAY_SIZE(s5p6442_spi0_resource),
  91         .resource         = s5p6442_spi0_resource,
  92         .dev = {
  93                 .dma_mask               = &spi_dmamask,
  94                 .coherent_dma_mask      = DMA_BIT_MASK(32),
  95                 .platform_data = &s5p6442_spi0_pdata,
  96         },
  97 };
  98
  99 void __init s5p6442_spi_set_info(int cntrlr, int src_clk_nr, int num_cs)
 100 {
 101         struct s3c64xx_spi_info *pd;
 102
 103         /* Reject invalid configuration */
 104         if (!num_cs || src_clk_nr < 0
 105                         || src_clk_nr > S5P6442_SPI_SRCCLK_SCLK) {
 106                 printk(KERN_ERR "%s: Invalid SPI configuration\n", __func__);
 107                 return;
 108         }
 109
 110         switch (cntrlr) {
 111         case 0:
 112                 pd = &s5p6442_spi0_pdata;
 113                 break;
 114         default:
 115                 printk(KERN_ERR "%s: Invalid SPI controller(%d)\n",
 116                                                         __func__, cntrlr);
 117                 return;
 118         }
 119
 120         pd->num_cs = num_cs;
 121         pd->src_clk_nr = src_clk_nr;
 122         pd->src_clk_name = spi_src_clks[src_clk_nr];
 123 }