drivers/mfd/intel_quark_i2c_gpio.c

   1 /*
   2  * Intel Quark MFD PCI driver for I2C & GPIO
   3  *
   4  * Copyright(c) 2014 Intel Corporation.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms and conditions of the GNU General Public License,
   8  * version 2, as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * Intel Quark PCI device for I2C and GPIO controller sharing the same
  16  * PCI function. This PCI driver will split the 2 devices into their
  17  * respective drivers.
  18  */
  19
  20 #include <linux/kernel.h>
  21 #include <linux/module.h>
  22 #include <linux/pci.h>
  23 #include <linux/mfd/core.h>
  24 #include <linux/clkdev.h>
  25 #include <linux/clk-provider.h>
  26 #include <linux/dmi.h>
  27 #include <linux/platform_data/gpio-dwapb.h>
  28 #include <linux/platform_data/i2c-designware.h>
  29
  30 /* PCI BAR for register base address */
  31 #define MFD_I2C_BAR             0
  32 #define MFD_GPIO_BAR            1
  33
  34 /* The base GPIO number under GPIOLIB framework */
  35 #define INTEL_QUARK_MFD_GPIO_BASE       8
  36
  37 /* The default number of South-Cluster GPIO on Quark. */
  38 #define INTEL_QUARK_MFD_NGPIO           8
  39
  40 /* The DesignWare GPIO ports on Quark. */
  41 #define INTEL_QUARK_GPIO_NPORTS 1
  42
  43 #define INTEL_QUARK_IORES_MEM   0
  44 #define INTEL_QUARK_IORES_IRQ   1
  45
  46 #define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
  47
  48 /* The Quark I2C controller source clock */
  49 #define INTEL_QUARK_I2C_CLK_HZ  33000000
  50
  51 #define INTEL_QUARK_I2C_NCLK    1
  52
  53 struct intel_quark_mfd {
  54         struct pci_dev          *pdev;
  55         struct clk              *i2c_clk;
  56         struct clk_lookup       *i2c_clk_lookup;
  57 };
  58
  59 struct i2c_mode_info {
  60         const char *name;
  61         unsigned int i2c_scl_freq;
  62 };
  63
  64 static const struct i2c_mode_info platform_i2c_mode_info[] = {
  65         {
  66                 .name = "Galileo",
  67                 .i2c_scl_freq = 100000,
  68         },
  69         {
  70                 .name = "GalileoGen2",
  71                 .i2c_scl_freq = 400000,
  72         },
  73         {}
  74 };
  75
  76 static struct resource intel_quark_i2c_res[] = {
  77         [INTEL_QUARK_IORES_MEM] = {
  78                 .flags = IORESOURCE_MEM,
  79         },
  80         [INTEL_QUARK_IORES_IRQ] = {
  81                 .flags = IORESOURCE_IRQ,
  82         },
  83 };
  84
  85 static struct resource intel_quark_gpio_res[] = {
  86         [INTEL_QUARK_IORES_MEM] = {
  87                 .flags = IORESOURCE_MEM,
  88         },
  89 };
  90
  91 static struct mfd_cell intel_quark_mfd_cells[] = {
  92         {
  93                 .id = MFD_I2C_BAR,
  94                 .name = "i2c_designware",
  95                 .num_resources = ARRAY_SIZE(intel_quark_i2c_res),
  96                 .resources = intel_quark_i2c_res,
  97                 .ignore_resource_conflicts = true,
  98         },
  99         {
 100                 .id = MFD_GPIO_BAR,
 101                 .name = "gpio-dwapb",
 102                 .num_resources = ARRAY_SIZE(intel_quark_gpio_res),
 103                 .resources = intel_quark_gpio_res,
 104                 .ignore_resource_conflicts = true,
 105         },
 106 };
 107
 108 static const struct pci_device_id intel_quark_mfd_ids[] = {
 109         { PCI_VDEVICE(INTEL, 0x0934), },
 110         {},
 111 };
 112 MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
 113
 114 static int intel_quark_register_i2c_clk(struct intel_quark_mfd *quark_mfd)
 115 {
 116         struct pci_dev *pdev = quark_mfd->pdev;
 117         struct clk_lookup *i2c_clk_lookup;
 118         struct clk *i2c_clk;
 119         int ret;
 120
 121         i2c_clk_lookup = devm_kcalloc(&pdev->dev, INTEL_QUARK_I2C_NCLK,
 122                                       sizeof(*i2c_clk_lookup), GFP_KERNEL);
 123         if (!i2c_clk_lookup)
 124                 return -ENOMEM;
 125
 126         i2c_clk_lookup[0].dev_id = INTEL_QUARK_I2C_CONTROLLER_CLK;
 127
 128         i2c_clk = clk_register_fixed_rate(&pdev->dev,
 129                                           INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
 130                                           CLK_IS_ROOT, INTEL_QUARK_I2C_CLK_HZ);
 131
 132         quark_mfd->i2c_clk_lookup = i2c_clk_lookup;
 133         quark_mfd->i2c_clk = i2c_clk;
 134
 135         ret = clk_register_clkdevs(i2c_clk, i2c_clk_lookup,
 136                                    INTEL_QUARK_I2C_NCLK);
 137         if (ret)
 138                 dev_err(&pdev->dev, "Fixed clk register failed: %d\n", ret);
 139
 140         return ret;
 141 }
 142
 143 static void intel_quark_unregister_i2c_clk(struct pci_dev *pdev)
 144 {
 145         struct intel_quark_mfd *quark_mfd = dev_get_drvdata(&pdev->dev);
 146
 147         if (!quark_mfd->i2c_clk || !quark_mfd->i2c_clk_lookup)
 148                 return;
 149
 150         clkdev_drop(quark_mfd->i2c_clk_lookup);
 151         clk_unregister(quark_mfd->i2c_clk);
 152 }
 153
 154 static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
 155 {
 156         const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
 157         const struct i2c_mode_info *info;
 158         struct dw_i2c_platform_data *pdata;
 159         struct resource *res = (struct resource *)cell->resources;
 160         struct device *dev = &pdev->dev;
 161
 162         res[INTEL_QUARK_IORES_MEM].start =
 163                 pci_resource_start(pdev, MFD_I2C_BAR);
 164         res[INTEL_QUARK_IORES_MEM].end =
 165                 pci_resource_end(pdev, MFD_I2C_BAR);
 166
 167         res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
 168         res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
 169
 170         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 171         if (!pdata)
 172                 return -ENOMEM;
 173
 174         /* Normal mode by default */
 175         pdata->i2c_scl_freq = 100000;
 176
 177         if (board_name) {
 178                 for (info = platform_i2c_mode_info; info->name; info++) {
 179                         if (!strcmp(board_name, info->name)) {
 180                                 pdata->i2c_scl_freq = info->i2c_scl_freq;
 181                                 break;
 182                         }
 183                 }
 184         }
 185
 186         cell->platform_data = pdata;
 187         cell->pdata_size = sizeof(*pdata);
 188
 189         return 0;
 190 }
 191
 192 static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
 193 {
 194         struct dwapb_platform_data *pdata;
 195         struct resource *res = (struct resource *)cell->resources;
 196         struct device *dev = &pdev->dev;
 197
 198         res[INTEL_QUARK_IORES_MEM].start =
 199                 pci_resource_start(pdev, MFD_GPIO_BAR);
 200         res[INTEL_QUARK_IORES_MEM].end =
 201                 pci_resource_end(pdev, MFD_GPIO_BAR);
 202
 203         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 204         if (!pdata)
 205                 return -ENOMEM;
 206
 207         /* For intel quark x1000, it has only one port: portA */
 208         pdata->nports = INTEL_QUARK_GPIO_NPORTS;
 209         pdata->properties = devm_kcalloc(dev, pdata->nports,
 210                                          sizeof(*pdata->properties),
 211                                          GFP_KERNEL);
 212         if (!pdata->properties)
 213                 return -ENOMEM;
 214
 215         /* Set the properties for portA */
 216         pdata->properties->node         = NULL;
 217         pdata->properties->name         = "intel-quark-x1000-gpio-portA";
 218         pdata->properties->idx          = 0;
 219         pdata->properties->ngpio        = INTEL_QUARK_MFD_NGPIO;
 220         pdata->properties->gpio_base    = INTEL_QUARK_MFD_GPIO_BASE;
 221         pdata->properties->irq          = pdev->irq;
 222         pdata->properties->irq_shared   = true;
 223
 224         cell->platform_data = pdata;
 225         cell->pdata_size = sizeof(*pdata);
 226
 227         return 0;
 228 }
 229
 230 static int intel_quark_mfd_probe(struct pci_dev *pdev,
 231                                  const struct pci_device_id *id)
 232 {
 233         struct intel_quark_mfd *quark_mfd;
 234         int ret;
 235
 236         ret = pcim_enable_device(pdev);
 237         if (ret)
 238                 return ret;
 239
 240         quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
 241         if (!quark_mfd)
 242                 return -ENOMEM;
 243         quark_mfd->pdev = pdev;
 244
 245         ret = intel_quark_register_i2c_clk(quark_mfd);
 246         if (ret)
 247                 return ret;
 248
 249         dev_set_drvdata(&pdev->dev, quark_mfd);
 250
 251         ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[MFD_I2C_BAR]);
 252         if (ret)
 253                 return ret;
 254
 255         ret = intel_quark_gpio_setup(pdev,
 256                                      &intel_quark_mfd_cells[MFD_GPIO_BAR]);
 257         if (ret)
 258                 return ret;
 259
 260         return mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
 261                                ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
 262                                NULL);
 263 }
 264
 265 static void intel_quark_mfd_remove(struct pci_dev *pdev)
 266 {
 267         intel_quark_unregister_i2c_clk(pdev);
 268         mfd_remove_devices(&pdev->dev);
 269 }
 270
 271 static struct pci_driver intel_quark_mfd_driver = {
 272         .name           = "intel_quark_mfd_i2c_gpio",
 273         .id_table       = intel_quark_mfd_ids,
 274         .probe          = intel_quark_mfd_probe,
 275         .remove         = intel_quark_mfd_remove,
 276 };
 277
 278 module_pci_driver(intel_quark_mfd_driver);
 279
 280 MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
 281 MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
 282 MODULE_LICENSE("GPL v2");