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 struct intel_quark_mfd {
  56         struct device           *dev;
  57         struct clk              *i2c_clk;
  58         struct clk_lookup       *i2c_clk_lookup;
  59 };
  60
  61 struct i2c_mode_info {
  62         const char *name;
  63         unsigned int i2c_scl_freq;
  64 };
  65
  66 static const struct i2c_mode_info platform_i2c_mode_info[] = {
  67         {
  68                 .name = "Galileo",
  69                 .i2c_scl_freq = 100000,
  70         },
  71         {
  72                 .name = "GalileoGen2",
  73                 .i2c_scl_freq = 400000,
  74         },
  75         {}
  76 };
  77
  78 static struct resource intel_quark_i2c_res[] = {
  79         [INTEL_QUARK_IORES_MEM] = {
  80                 .flags = IORESOURCE_MEM,
  81         },
  82         [INTEL_QUARK_IORES_IRQ] = {
  83                 .flags = IORESOURCE_IRQ,
  84         },
  85 };
  86
  87 static struct mfd_cell_acpi_match intel_quark_acpi_match_i2c = {
  88         .adr = MFD_ACPI_MATCH_I2C,
  89 };
  90
  91 static struct resource intel_quark_gpio_res[] = {
  92         [INTEL_QUARK_IORES_MEM] = {
  93                 .flags = IORESOURCE_MEM,
  94         },
  95 };
  96
  97 static struct mfd_cell_acpi_match intel_quark_acpi_match_gpio = {
  98         .adr = MFD_ACPI_MATCH_GPIO,
  99 };
 100
 101 static struct mfd_cell intel_quark_mfd_cells[] = {
 102         {
 103                 .id = MFD_GPIO_BAR,
 104                 .name = "gpio-dwapb",
 105                 .acpi_match = &intel_quark_acpi_match_gpio,
 106                 .num_resources = ARRAY_SIZE(intel_quark_gpio_res),
 107                 .resources = intel_quark_gpio_res,
 108                 .ignore_resource_conflicts = true,
 109         },
 110         {
 111                 .id = MFD_I2C_BAR,
 112                 .name = "i2c_designware",
 113                 .acpi_match = &intel_quark_acpi_match_i2c,
 114                 .num_resources = ARRAY_SIZE(intel_quark_i2c_res),
 115                 .resources = intel_quark_i2c_res,
 116                 .ignore_resource_conflicts = true,
 117         },
 118 };
 119
 120 static const struct pci_device_id intel_quark_mfd_ids[] = {
 121         { PCI_VDEVICE(INTEL, 0x0934), },
 122         {},
 123 };
 124 MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
 125
 126 static int intel_quark_register_i2c_clk(struct device *dev)
 127 {
 128         struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
 129         struct clk *i2c_clk;
 130
 131         i2c_clk = clk_register_fixed_rate(dev,
 132                                           INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
 133                                           0, INTEL_QUARK_I2C_CLK_HZ);
 134         if (IS_ERR(i2c_clk))
 135                 return PTR_ERR(i2c_clk);
 136
 137         quark_mfd->i2c_clk = i2c_clk;
 138         quark_mfd->i2c_clk_lookup = clkdev_create(i2c_clk, NULL,
 139                                                 INTEL_QUARK_I2C_CONTROLLER_CLK);
 140
 141         if (!quark_mfd->i2c_clk_lookup) {
 142                 clk_unregister(quark_mfd->i2c_clk);
 143                 dev_err(dev, "Fixed clk register failed\n");
 144                 return -ENOMEM;
 145         }
 146
 147         return 0;
 148 }
 149
 150 static void intel_quark_unregister_i2c_clk(struct device *dev)
 151 {
 152         struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
 153
 154         if (!quark_mfd->i2c_clk_lookup)
 155                 return;
 156
 157         clkdev_drop(quark_mfd->i2c_clk_lookup);
 158         clk_unregister(quark_mfd->i2c_clk);
 159 }
 160
 161 static int intel_quark_i2c_setup(struct pci_dev *pdev, struct mfd_cell *cell)
 162 {
 163         const char *board_name = dmi_get_system_info(DMI_BOARD_NAME);
 164         const struct i2c_mode_info *info;
 165         struct dw_i2c_platform_data *pdata;
 166         struct resource *res = (struct resource *)cell->resources;
 167         struct device *dev = &pdev->dev;
 168
 169         res[INTEL_QUARK_IORES_MEM].start =
 170                 pci_resource_start(pdev, MFD_I2C_BAR);
 171         res[INTEL_QUARK_IORES_MEM].end =
 172                 pci_resource_end(pdev, MFD_I2C_BAR);
 173
 174         res[INTEL_QUARK_IORES_IRQ].start = pdev->irq;
 175         res[INTEL_QUARK_IORES_IRQ].end = pdev->irq;
 176
 177         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 178         if (!pdata)
 179                 return -ENOMEM;
 180
 181         /* Normal mode by default */
 182         pdata->i2c_scl_freq = 100000;
 183
 184         if (board_name) {
 185                 for (info = platform_i2c_mode_info; info->name; info++) {
 186                         if (!strcmp(board_name, info->name)) {
 187                                 pdata->i2c_scl_freq = info->i2c_scl_freq;
 188                                 break;
 189                         }
 190                 }
 191         }
 192
 193         cell->platform_data = pdata;
 194         cell->pdata_size = sizeof(*pdata);
 195
 196         return 0;
 197 }
 198
 199 static int intel_quark_gpio_setup(struct pci_dev *pdev, struct mfd_cell *cell)
 200 {
 201         struct dwapb_platform_data *pdata;
 202         struct resource *res = (struct resource *)cell->resources;
 203         struct device *dev = &pdev->dev;
 204
 205         res[INTEL_QUARK_IORES_MEM].start =
 206                 pci_resource_start(pdev, MFD_GPIO_BAR);
 207         res[INTEL_QUARK_IORES_MEM].end =
 208                 pci_resource_end(pdev, MFD_GPIO_BAR);
 209
 210         pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
 211         if (!pdata)
 212                 return -ENOMEM;
 213
 214         /* For intel quark x1000, it has only one port: portA */
 215         pdata->nports = INTEL_QUARK_GPIO_NPORTS;
 216         pdata->properties = devm_kcalloc(dev, pdata->nports,
 217                                          sizeof(*pdata->properties),
 218                                          GFP_KERNEL);
 219         if (!pdata->properties)
 220                 return -ENOMEM;
 221
 222         /* Set the properties for portA */
 223         pdata->properties->fwnode       = NULL;
 224         pdata->properties->idx          = 0;
 225         pdata->properties->ngpio        = INTEL_QUARK_MFD_NGPIO;
 226         pdata->properties->gpio_base    = INTEL_QUARK_MFD_GPIO_BASE;
 227         pdata->properties->irq          = pdev->irq;
 228         pdata->properties->irq_shared   = true;
 229
 230         cell->platform_data = pdata;
 231         cell->pdata_size = sizeof(*pdata);
 232
 233         return 0;
 234 }
 235
 236 static int intel_quark_mfd_probe(struct pci_dev *pdev,
 237                                  const struct pci_device_id *id)
 238 {
 239         struct intel_quark_mfd *quark_mfd;
 240         int ret;
 241
 242         ret = pcim_enable_device(pdev);
 243         if (ret)
 244                 return ret;
 245
 246         quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
 247         if (!quark_mfd)
 248                 return -ENOMEM;
 249
 250         quark_mfd->dev = &pdev->dev;
 251         dev_set_drvdata(&pdev->dev, quark_mfd);
 252
 253         ret = intel_quark_register_i2c_clk(&pdev->dev);
 254         if (ret)
 255                 return ret;
 256
 257         ret = intel_quark_i2c_setup(pdev, &intel_quark_mfd_cells[1]);
 258         if (ret)
 259                 goto err_unregister_i2c_clk;
 260
 261         ret = intel_quark_gpio_setup(pdev, &intel_quark_mfd_cells[0]);
 262         if (ret)
 263                 goto err_unregister_i2c_clk;
 264
 265         ret = mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
 266                               ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
 267                               NULL);
 268         if (ret)
 269                 goto err_unregister_i2c_clk;
 270
 271         return 0;
 272
 273 err_unregister_i2c_clk:
 274         intel_quark_unregister_i2c_clk(&pdev->dev);
 275         return ret;
 276 }
 277
 278 static void intel_quark_mfd_remove(struct pci_dev *pdev)
 279 {
 280         intel_quark_unregister_i2c_clk(&pdev->dev);
 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");