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 /* ACPI _ADR value to match the child node */
  35 #define MFD_ACPI_MATCH_GPIO     0ULL
  36 #define MFD_ACPI_MATCH_I2C      1ULL
  37
  38 /* The base GPIO number under GPIOLIB framework */
  39 #define INTEL_QUARK_MFD_GPIO_BASE       8
  40
  41 /* The default number of South-Cluster GPIO on Quark. */
  42 #define INTEL_QUARK_MFD_NGPIO           8
  43
  44 /* The DesignWare GPIO ports on Quark. */
  45 #define INTEL_QUARK_GPIO_NPORTS 1
  46
  47 #define INTEL_QUARK_IORES_MEM   0
  48 #define INTEL_QUARK_IORES_IRQ   1
  49
  50 #define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
  51
  52 /* The Quark I2C controller source clock */
  53 #define INTEL_QUARK_I2C_CLK_HZ  33000000
  54
  55 #define INTEL_QUARK_I2C_NCLK    1
  56
  57 struct intel_quark_mfd {
  58         struct pci_dev          *pdev;
  59         struct clk              *i2c_clk;
  60         struct clk_lookup       *i2c_clk_lookup;
  61 };
  62
  63 struct i2c_mode_info {
  64         const char *name;
  65         unsigned int i2c_scl_freq;
  66 };
  67
  68 static const struct i2c_mode_info platform_i2c_mode_info[] = {
  69         {
  70                 .name = "Galileo",
  71                 .i2c_scl_freq = 100000,
  72         },
  73         {
  74                 .name = "GalileoGen2",
  75                 .i2c_scl_freq = 400000,
  76         },
  77         {}
  78 };
  79
  80 static struct resource intel_quark_i2c_res[] = {
  81         [INTEL_QUARK_IORES_MEM] = {
  82                 .flags = IORESOURCE_MEM,
  83         },
  84         [INTEL_QUARK_IORES_IRQ] = {
  85                 .flags = IORESOURCE_IRQ,
  86         },
  87 };
  88
  89 static struct mfd_cell_acpi_match intel_quark_acpi_match_i2c = {
  90         .adr = MFD_ACPI_MATCH_I2C,
  91 };
  92
  93 static struct resource intel_quark_gpio_res[] = {
  94         [INTEL_QUARK_IORES_MEM] = {
  95                 .flags = IORESOURCE_MEM,
  96         },
  97 };
  98
  99 static struct mfd_cell_acpi_match intel_quark_acpi_match_gpio = {
 100         .adr = MFD_ACPI_MATCH_GPIO,
 101 };
 102
 103 static struct mfd_cell intel_quark_mfd_cells[] = {
 104         {
 105                 .id = MFD_GPIO_BAR,
 106                 .name = "gpio-dwapb",
 107                 .acpi_match = &intel_quark_acpi_match_gpio,
 108                 .num_resources = ARRAY_SIZE(intel_quark_gpio_res),
 109                 .resources = intel_quark_gpio_res,
 110                 .ignore_resource_conflicts = true,
 111         },
 112         {
 113                 .id = MFD_I2C_BAR,
 114                 .name = "i2c_designware",
 115                 .acpi_match = &intel_quark_acpi_match_i2c,
 116                 .num_resources = ARRAY_SIZE(intel_quark_i2c_res),
 117                 .resources = intel_quark_i2c_res,
 118                 .ignore_resource_conflicts = true,
 119         },
 120 };
 121
 122 static const struct pci_device_id intel_quark_mfd_ids[] = {
 123         { PCI_VDEVICE(INTEL, 0x0934), },
 124         {},
 125 };
 126 MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
 127
 128 static int intel_quark_register_i2c_clk(struct intel_quark_mfd *quark_mfd)
 129 {
 130         struct pci_dev *pdev = quark_mfd->pdev;
 131         struct clk_lookup *i2c_clk_lookup;
 132         struct clk *i2c_clk;
 133         int ret;
 134
 135         i2c_clk_lookup = devm_kcalloc(&pdev->dev, INTEL_QUARK_I2C_NCLK,
 136                                       sizeof(*i2c_clk_lookup), GFP_KERNEL);
 137         if (!i2c_clk_lookup)
 138                 return -ENOMEM;
 139
 140         i2c_clk_lookup[0].dev_id = INTEL_QUARK_I2C_CONTROLLER_CLK;
 141
 142         i2c_clk = clk_register_fixed_rate(&pdev->dev,
 143                                           INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
 144                                           CLK_IS_ROOT, INTEL_QUARK_I2C_CLK_HZ);
 145
 146         quark_mfd->i2c_clk_lookup = i2c_clk_lookup;
 147         quark_mfd->i2c_clk = i2c_clk;
 148
 149         ret = clk_register_clkdevs(i2c_clk, i2c_clk_lookup,
 150                                    INTEL_QUARK_I2C_NCLK);
 151         if (ret)
 152                 dev_err(&pdev->dev, "Fixed clk register failed: %d\n", ret);
 153
 154         return ret;
 155 }
 156
 157 static void intel_quark_unregister_i2c_clk(struct pci_dev *pdev)
 158 {
 159         struct intel_quark_mfd *quark_mfd = dev_get_drvdata(&pdev->dev);
 160
 161         if (!quark_mfd->i2c_clk || !quark_mfd->i2c_clk_lookup)
 162                 return;
 163
 164         clkdev_drop(quark_mfd->i2c_clk_lookup);
 165         clk_unregister(quark_mfd->i2c_clk);
 166 }
 167
 168 static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
 169 {
 170         const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
 171         const struct i2c_mode_info *info;
 172         struct dw_i2c_platform_data *pdata;
 173         struct resource *res = (struct resource *)cell->resources;
 174         struct device *dev = &pdev->dev;
 175
 176         res[INTEL_QUARK_IORES_MEM].start =
 177                 pci_resource_start(pdev, MFD_I2C_BAR);
 178         res[INTEL_QUARK_IORES_MEM].end =
 179                 pci_resource_end(pdev, MFD_I2C_BAR);
 180
 181         res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
 182         res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
 183
 184         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 185         if (!pdata)
 186                 return -ENOMEM;
 187
 188         /* Normal mode by default */
 189         pdata->i2c_scl_freq = 100000;
 190
 191         if (board_name) {
 192                 for (info = platform_i2c_mode_info; info->name; info++) {
 193                         if (!strcmp(board_name, info->name)) {
 194                                 pdata->i2c_scl_freq = info->i2c_scl_freq;
 195                                 break;
 196                         }
 197                 }
 198         }
 199
 200         cell->platform_data = pdata;
 201         cell->pdata_size = sizeof(*pdata);
 202
 203         return 0;
 204 }
 205
 206 static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
 207 {
 208         struct dwapb_platform_data *pdata;
 209         struct resource *res = (struct resource *)cell->resources;
 210         struct device *dev = &pdev->dev;
 211
 212         res[INTEL_QUARK_IORES_MEM].start =
 213                 pci_resource_start(pdev, MFD_GPIO_BAR);
 214         res[INTEL_QUARK_IORES_MEM].end =
 215                 pci_resource_end(pdev, MFD_GPIO_BAR);
 216
 217         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 218         if (!pdata)
 219                 return -ENOMEM;
 220
 221         /* For intel quark x1000, it has only one port: portA */
 222         pdata->nports = INTEL_QUARK_GPIO_NPORTS;
 223         pdata->properties = devm_kcalloc(dev, pdata->nports,
 224                                          sizeof(*pdata->properties),
 225                                          GFP_KERNEL);
 226         if (!pdata->properties)
 227                 return -ENOMEM;
 228
 229         /* Set the properties for portA */
 230         pdata->properties->node         = NULL;
 231         pdata->properties->name         = "intel-quark-x1000-gpio-portA";
 232         pdata->properties->idx          = 0;
 233         pdata->properties->ngpio        = INTEL_QUARK_MFD_NGPIO;
 234         pdata->properties->gpio_base    = INTEL_QUARK_MFD_GPIO_BASE;
 235         pdata->properties->irq          = pdev->irq;
 236         pdata->properties->irq_shared   = true;
 237
 238         cell->platform_data = pdata;
 239         cell->pdata_size = sizeof(*pdata);
 240
 241         return 0;
 242 }
 243
 244 static int intel_quark_mfd_probe(struct pci_dev *pdev,
 245                                  const struct pci_device_id *id)
 246 {
 247         struct intel_quark_mfd *quark_mfd;
 248         int ret;
 249
 250         ret = pcim_enable_device(pdev);
 251         if (ret)
 252                 return ret;
 253
 254         quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
 255         if (!quark_mfd)
 256                 return -ENOMEM;
 257         quark_mfd->pdev = pdev;
 258
 259         ret = intel_quark_register_i2c_clk(quark_mfd);
 260         if (ret)
 261                 return ret;
 262
 263         dev_set_drvdata(&pdev->dev, quark_mfd);
 264
 265         ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[1]);
 266         if (ret)
 267                 return ret;
 268
 269         ret = intel_quark_gpio_setup(pdev, &intel_quark_mfd_cells[0]);
 270         if (ret)
 271                 return ret;
 272
 273         return mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
 274                                ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
 275                                NULL);
 276 }
 277
 278 static void intel_quark_mfd_remove(struct pci_dev *pdev)
 279 {
 280         intel_quark_unregister_i2c_clk(pdev);
 281         mfd_remove_devices(&pdev->dev);
 282 }
 283
 284 static struct pci_driver intel_quark_mfd_driver = {
 285         .name           = "intel_quark_mfd_i2c_gpio",
 286         .id_table       = intel_quark_mfd_ids,
 287         .probe          = intel_quark_mfd_probe,
 288         .remove         = intel_quark_mfd_remove,
 289 };
 290
 291 module_pci_driver(intel_quark_mfd_driver);
 292
 293 MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
 294 MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
 295 MODULE_LICENSE("GPL v2");