drivers/gpio/gpio-mlxbf.c

   1 // SPDX-License-Identifier: GPL-2.0
   2
   3 #include <linux/acpi.h>
   4 #include <linux/bitops.h>
   5 #include <linux/device.h>
   6 #include <linux/gpio/driver.h>
   7 #include <linux/io.h>
   8 #include <linux/kernel.h>
   9 #include <linux/module.h>
  10 #include <linux/platform_device.h>
  11 #include <linux/pm.h>
  12 #include <linux/resource.h>
  13 #include <linux/types.h>
  14
  15 /* Number of pins on BlueField */
  16 #define MLXBF_GPIO_NR 54
  17
  18 /* Pad Electrical Controls. */
  19 #define MLXBF_GPIO_PAD_CONTROL_FIRST_WORD 0x0700
  20 #define MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD 0x0708
  21 #define MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD 0x0710
  22 #define MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD 0x0718
  23
  24 #define MLXBF_GPIO_PIN_DIR_I 0x1040
  25 #define MLXBF_GPIO_PIN_DIR_O 0x1048
  26 #define MLXBF_GPIO_PIN_STATE 0x1000
  27 #define MLXBF_GPIO_SCRATCHPAD 0x20
  28
  29 #ifdef CONFIG_PM
  30 struct mlxbf_gpio_context_save_regs {
  31         u64 scratchpad;
  32         u64 pad_control[MLXBF_GPIO_NR];
  33         u64 pin_dir_i;
  34         u64 pin_dir_o;
  35 };
  36 #endif
  37
  38 /* Device state structure. */
  39 struct mlxbf_gpio_state {
  40         struct gpio_chip gc;
  41
  42         /* Memory Address */
  43         void __iomem *base;
  44
  45 #ifdef CONFIG_PM
  46         struct mlxbf_gpio_context_save_regs csave_regs;
  47 #endif
  48 };
  49
  50 static int mlxbf_gpio_probe(struct platform_device *pdev)
  51 {
  52         struct mlxbf_gpio_state *gs;
  53         struct device *dev = &pdev->dev;
  54         struct gpio_chip *gc;
  55         int ret;
  56
  57         gs = devm_kzalloc(&pdev->dev, sizeof(*gs), GFP_KERNEL);
  58         if (!gs)
  59                 return -ENOMEM;
  60
  61         gs->base = devm_platform_ioremap_resource(pdev, 0);
  62         if (IS_ERR(gs->base))
  63                 return PTR_ERR(gs->base);
  64
  65         gc = &gs->gc;
  66         ret = bgpio_init(gc, dev, 8,
  67                          gs->base + MLXBF_GPIO_PIN_STATE,
  68                          NULL,
  69                          NULL,
  70                          gs->base + MLXBF_GPIO_PIN_DIR_O,
  71                          gs->base + MLXBF_GPIO_PIN_DIR_I,
  72                          0);
  73         if (ret)
  74                 return -ENODEV;
  75
  76         gc->owner = THIS_MODULE;
  77         gc->ngpio = MLXBF_GPIO_NR;
  78
  79         ret = devm_gpiochip_add_data(dev, &gs->gc, gs);
  80         if (ret) {
  81                 dev_err(&pdev->dev, "Failed adding memory mapped gpiochip\n");
  82                 return ret;
  83         }
  84
  85         platform_set_drvdata(pdev, gs);
  86         dev_info(&pdev->dev, "registered Mellanox BlueField GPIO");
  87         return 0;
  88 }
  89
  90 #ifdef CONFIG_PM
  91 static int mlxbf_gpio_suspend(struct platform_device *pdev, pm_message_t state)
  92 {
  93         struct mlxbf_gpio_state *gs = platform_get_drvdata(pdev);
  94
  95         gs->csave_regs.scratchpad = readq(gs->base + MLXBF_GPIO_SCRATCHPAD);
  96         gs->csave_regs.pad_control[0] =
  97                 readq(gs->base + MLXBF_GPIO_PAD_CONTROL_FIRST_WORD);
  98         gs->csave_regs.pad_control[1] =
  99                 readq(gs->base + MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD);
 100         gs->csave_regs.pad_control[2] =
 101                 readq(gs->base + MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD);
 102         gs->csave_regs.pad_control[3] =
 103                 readq(gs->base + MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD);
 104         gs->csave_regs.pin_dir_i = readq(gs->base + MLXBF_GPIO_PIN_DIR_I);
 105         gs->csave_regs.pin_dir_o = readq(gs->base + MLXBF_GPIO_PIN_DIR_O);
 106
 107         return 0;
 108 }
 109
 110 static int mlxbf_gpio_resume(struct platform_device *pdev)
 111 {
 112         struct mlxbf_gpio_state *gs = platform_get_drvdata(pdev);
 113
 114         writeq(gs->csave_regs.scratchpad, gs->base + MLXBF_GPIO_SCRATCHPAD);
 115         writeq(gs->csave_regs.pad_control[0],
 116                gs->base + MLXBF_GPIO_PAD_CONTROL_FIRST_WORD);
 117         writeq(gs->csave_regs.pad_control[1],
 118                gs->base + MLXBF_GPIO_PAD_CONTROL_1_FIRST_WORD);
 119         writeq(gs->csave_regs.pad_control[2],
 120                gs->base + MLXBF_GPIO_PAD_CONTROL_2_FIRST_WORD);
 121         writeq(gs->csave_regs.pad_control[3],
 122                gs->base + MLXBF_GPIO_PAD_CONTROL_3_FIRST_WORD);
 123         writeq(gs->csave_regs.pin_dir_i, gs->base + MLXBF_GPIO_PIN_DIR_I);
 124         writeq(gs->csave_regs.pin_dir_o, gs->base + MLXBF_GPIO_PIN_DIR_O);
 125
 126         return 0;
 127 }
 128 #endif
 129
 130 static const struct acpi_device_id __maybe_unused mlxbf_gpio_acpi_match[] = {
 131         { "MLNXBF02", 0 },
 132         {}
 133 };
 134 MODULE_DEVICE_TABLE(acpi, mlxbf_gpio_acpi_match);
 135
 136 static struct platform_driver mlxbf_gpio_driver = {
 137         .driver = {
 138                 .name = "mlxbf_gpio",
 139                 .acpi_match_table = ACPI_PTR(mlxbf_gpio_acpi_match),
 140         },
 141         .probe    = mlxbf_gpio_probe,
 142 #ifdef CONFIG_PM
 143         .suspend  = mlxbf_gpio_suspend,
 144         .resume   = mlxbf_gpio_resume,
 145 #endif
 146 };
 147
 148 module_platform_driver(mlxbf_gpio_driver);
 149
 150 MODULE_DESCRIPTION("Mellanox BlueField GPIO Driver");
 151 MODULE_AUTHOR("Mellanox Technologies");
 152 MODULE_LICENSE("GPL");