linux/drivers/mfd/intel_quark_i2c_gpio.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Intel Quark MFD PCI driver for I2C & GPIO
   4 *
   5 * Copyright(c) 2014 Intel Corporation.
   6 *
   7 * Intel Quark PCI device for I2C and GPIO controller sharing the same
   8 * PCI function. This PCI driver will split the 2 devices into their
   9 * respective drivers.
  10 */
  11
  12#include <linux/kernel.h>
  13#include <linux/module.h>
  14#include <linux/pci.h>
  15#include <linux/mfd/core.h>
  16#include <linux/clkdev.h>
  17#include <linux/clk-provider.h>
  18#include <linux/dmi.h>
  19#include <linux/i2c.h>
  20#include <linux/property.h>
  21
  22/* PCI BAR for register base address */
  23#define MFD_I2C_BAR             0
  24#define MFD_GPIO_BAR            1
  25
  26/* ACPI _ADR value to match the child node */
  27#define MFD_ACPI_MATCH_GPIO     0ULL
  28#define MFD_ACPI_MATCH_I2C      1ULL
  29
  30#define INTEL_QUARK_IORES_MEM   0
  31#define INTEL_QUARK_IORES_IRQ   1
  32
  33#define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
  34
  35/* The Quark I2C controller source clock */
  36#define INTEL_QUARK_I2C_CLK_HZ  33000000
  37
  38struct intel_quark_mfd {
  39        struct clk              *i2c_clk;
  40        struct clk_lookup       *i2c_clk_lookup;
  41};
  42
  43static const struct property_entry intel_quark_i2c_controller_standard_properties[] = {
  44        PROPERTY_ENTRY_U32("clock-frequency", I2C_MAX_STANDARD_MODE_FREQ),
  45        { }
  46};
  47
  48static const struct software_node intel_quark_i2c_controller_standard_node = {
  49        .name = "intel-quark-i2c-controller",
  50        .properties = intel_quark_i2c_controller_standard_properties,
  51};
  52
  53static const struct property_entry intel_quark_i2c_controller_fast_properties[] = {
  54        PROPERTY_ENTRY_U32("clock-frequency", I2C_MAX_FAST_MODE_FREQ),
  55        { }
  56};
  57
  58static const struct software_node intel_quark_i2c_controller_fast_node = {
  59        .name = "intel-quark-i2c-controller",
  60        .properties = intel_quark_i2c_controller_fast_properties,
  61};
  62
  63static const struct dmi_system_id dmi_platform_info[] = {
  64        {
  65                .matches = {
  66                        DMI_EXACT_MATCH(DMI_BOARD_NAME, "Galileo"),
  67                },
  68                .driver_data = (void *)&intel_quark_i2c_controller_standard_node,
  69        },
  70        {
  71                .matches = {
  72                        DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
  73                },
  74                .driver_data = (void *)&intel_quark_i2c_controller_fast_node,
  75        },
  76        {
  77                .matches = {
  78                        DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
  79                },
  80                .driver_data = (void *)&intel_quark_i2c_controller_fast_node,
  81        },
  82        {}
  83};
  84
  85/* This is used as a place holder and will be modified at run-time */
  86static struct resource intel_quark_i2c_res[] = {
  87        [INTEL_QUARK_IORES_MEM] = {
  88                .flags = IORESOURCE_MEM,
  89        },
  90        [INTEL_QUARK_IORES_IRQ] = {
  91                .flags = IORESOURCE_IRQ,
  92        },
  93};
  94
  95static struct mfd_cell_acpi_match intel_quark_acpi_match_i2c = {
  96        .adr = MFD_ACPI_MATCH_I2C,
  97};
  98
  99/* This is used as a place holder and will be modified at run-time */
 100static struct resource intel_quark_gpio_res[] = {
 101        [INTEL_QUARK_IORES_MEM] = {
 102                .flags = IORESOURCE_MEM,
 103        },
 104        [INTEL_QUARK_IORES_IRQ] = {
 105                .flags = IORESOURCE_IRQ,
 106        },
 107};
 108
 109static struct mfd_cell_acpi_match intel_quark_acpi_match_gpio = {
 110        .adr = MFD_ACPI_MATCH_GPIO,
 111};
 112
 113static const struct software_node intel_quark_gpio_controller_node = {
 114        .name = "intel-quark-gpio-controller",
 115};
 116
 117static const struct property_entry intel_quark_gpio_portA_properties[] = {
 118        PROPERTY_ENTRY_U32("reg", 0),
 119        PROPERTY_ENTRY_U32("snps,nr-gpios", 8),
 120        PROPERTY_ENTRY_U32("gpio-base", 8),
 121        { }
 122};
 123
 124static const struct software_node intel_quark_gpio_portA_node = {
 125        .name = "portA",
 126        .parent = &intel_quark_gpio_controller_node,
 127        .properties = intel_quark_gpio_portA_properties,
 128};
 129
 130static const struct software_node *intel_quark_gpio_node_group[] = {
 131        &intel_quark_gpio_controller_node,
 132        &intel_quark_gpio_portA_node,
 133        NULL
 134};
 135
 136static struct mfd_cell intel_quark_mfd_cells[] = {
 137        [MFD_I2C_BAR] = {
 138                .id = MFD_I2C_BAR,
 139                .name = "i2c_designware",
 140                .acpi_match = &intel_quark_acpi_match_i2c,
 141                .num_resources = ARRAY_SIZE(intel_quark_i2c_res),
 142                .resources = intel_quark_i2c_res,
 143                .ignore_resource_conflicts = true,
 144        },
 145        [MFD_GPIO_BAR] = {
 146                .id = MFD_GPIO_BAR,
 147                .name = "gpio-dwapb",
 148                .acpi_match = &intel_quark_acpi_match_gpio,
 149                .num_resources = ARRAY_SIZE(intel_quark_gpio_res),
 150                .resources = intel_quark_gpio_res,
 151                .ignore_resource_conflicts = true,
 152        },
 153};
 154
 155static const struct pci_device_id intel_quark_mfd_ids[] = {
 156        { PCI_VDEVICE(INTEL, 0x0934), },
 157        {},
 158};
 159MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
 160
 161static int intel_quark_register_i2c_clk(struct device *dev)
 162{
 163        struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
 164        struct clk *i2c_clk;
 165
 166        i2c_clk = clk_register_fixed_rate(dev,
 167                                          INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
 168                                          0, INTEL_QUARK_I2C_CLK_HZ);
 169        if (IS_ERR(i2c_clk))
 170                return PTR_ERR(i2c_clk);
 171
 172        quark_mfd->i2c_clk = i2c_clk;
 173        quark_mfd->i2c_clk_lookup = clkdev_create(i2c_clk, NULL,
 174                                                INTEL_QUARK_I2C_CONTROLLER_CLK);
 175
 176        if (!quark_mfd->i2c_clk_lookup) {
 177                clk_unregister(quark_mfd->i2c_clk);
 178                dev_err(dev, "Fixed clk register failed\n");
 179                return -ENOMEM;
 180        }
 181
 182        return 0;
 183}
 184
 185static void intel_quark_unregister_i2c_clk(struct device *dev)
 186{
 187        struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
 188
 189        if (!quark_mfd->i2c_clk_lookup)
 190                return;
 191
 192        clkdev_drop(quark_mfd->i2c_clk_lookup);
 193        clk_unregister(quark_mfd->i2c_clk);
 194}
 195
 196static int intel_quark_i2c_setup(struct pci_dev *pdev)
 197{
 198        struct mfd_cell *cell = &intel_quark_mfd_cells[MFD_I2C_BAR];
 199        struct resource *res = intel_quark_i2c_res;
 200        const struct dmi_system_id *dmi_id;
 201
 202        res[INTEL_QUARK_IORES_MEM].start = pci_resource_start(pdev, MFD_I2C_BAR);
 203        res[INTEL_QUARK_IORES_MEM].end = pci_resource_end(pdev, MFD_I2C_BAR);
 204
 205        res[INTEL_QUARK_IORES_IRQ].start = pci_irq_vector(pdev, 0);
 206        res[INTEL_QUARK_IORES_IRQ].end = pci_irq_vector(pdev, 0);
 207
 208        /* Normal mode by default */
 209        cell->swnode = &intel_quark_i2c_controller_standard_node;
 210
 211        dmi_id = dmi_first_match(dmi_platform_info);
 212        if (dmi_id)
 213                cell->swnode = (struct software_node *)dmi_id->driver_data;
 214
 215        return 0;
 216}
 217
 218static int intel_quark_gpio_setup(struct pci_dev *pdev)
 219{
 220        struct mfd_cell *cell = &intel_quark_mfd_cells[MFD_GPIO_BAR];
 221        struct resource *res = intel_quark_gpio_res;
 222        int ret;
 223
 224        res[INTEL_QUARK_IORES_MEM].start = pci_resource_start(pdev, MFD_GPIO_BAR);
 225        res[INTEL_QUARK_IORES_MEM].end = pci_resource_end(pdev, MFD_GPIO_BAR);
 226
 227        res[INTEL_QUARK_IORES_IRQ].start = pci_irq_vector(pdev, 0);
 228        res[INTEL_QUARK_IORES_IRQ].end = pci_irq_vector(pdev, 0);
 229
 230        ret = software_node_register_node_group(intel_quark_gpio_node_group);
 231        if (ret)
 232                return ret;
 233
 234        cell->swnode = &intel_quark_gpio_controller_node;
 235        return 0;
 236}
 237
 238static int intel_quark_mfd_probe(struct pci_dev *pdev,
 239                                 const struct pci_device_id *id)
 240{
 241        struct intel_quark_mfd *quark_mfd;
 242        int ret;
 243
 244        ret = pcim_enable_device(pdev);
 245        if (ret)
 246                return ret;
 247
 248        quark_mfd = devm_kzalloc(&pdev->dev, sizeof(*quark_mfd), GFP_KERNEL);
 249        if (!quark_mfd)
 250                return -ENOMEM;
 251
 252        dev_set_drvdata(&pdev->dev, quark_mfd);
 253
 254        ret = intel_quark_register_i2c_clk(&pdev->dev);
 255        if (ret)
 256                return ret;
 257
 258        pci_set_master(pdev);
 259
 260        /* This driver only requires 1 IRQ vector */
 261        ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES);
 262        if (ret < 0)
 263                goto err_unregister_i2c_clk;
 264
 265        ret = intel_quark_i2c_setup(pdev);
 266        if (ret)
 267                goto err_free_irq_vectors;
 268
 269        ret = intel_quark_gpio_setup(pdev);
 270        if (ret)
 271                goto err_free_irq_vectors;
 272
 273        ret = mfd_add_devices(&pdev->dev, 0, intel_quark_mfd_cells,
 274                              ARRAY_SIZE(intel_quark_mfd_cells), NULL, 0,
 275                              NULL);
 276        if (ret)
 277                goto err_unregister_gpio_node_group;
 278
 279        return 0;
 280
 281err_unregister_gpio_node_group:
 282        software_node_unregister_node_group(intel_quark_gpio_node_group);
 283err_free_irq_vectors:
 284        pci_free_irq_vectors(pdev);
 285err_unregister_i2c_clk:
 286        intel_quark_unregister_i2c_clk(&pdev->dev);
 287        return ret;
 288}
 289
 290static void intel_quark_mfd_remove(struct pci_dev *pdev)
 291{
 292        mfd_remove_devices(&pdev->dev);
 293        software_node_unregister_node_group(intel_quark_gpio_node_group);
 294        pci_free_irq_vectors(pdev);
 295        intel_quark_unregister_i2c_clk(&pdev->dev);
 296}
 297
 298static struct pci_driver intel_quark_mfd_driver = {
 299        .name           = "intel_quark_mfd_i2c_gpio",
 300        .id_table       = intel_quark_mfd_ids,
 301        .probe          = intel_quark_mfd_probe,
 302        .remove         = intel_quark_mfd_remove,
 303};
 304
 305module_pci_driver(intel_quark_mfd_driver);
 306
 307MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
 308MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
 309MODULE_LICENSE("GPL v2");
 310