git.openwrt.org Git - openwrt/staging/xback.git/blob

   1 From 512c5be35223d9baa2629efa1084cf5210eaee80 Mon Sep 17 00:00:00 2001
   2 From: Sander Vanheule <sander@svanheule.net>
   3 Date: Sat, 9 Apr 2022 21:55:47 +0200
   4 Subject: [PATCH 2/6] gpio: realtek-otto: Support reversed port layouts
   5
   6 The GPIO port layout on the RTL930x SoC series is reversed compared to
   7 the RTL838x and RTL839x SoC series. Add new port offset calculator
   8 functions to ensure the correct order is used when reading port IRQ
   9 data, and ensure bgpio uses the right byte ordering.
  10
  11 Signed-off-by: Sander Vanheule <sander@svanheule.net>
  12 Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
  13 ---
  14  drivers/gpio/gpio-realtek-otto.c | 55 +++++++++++++++++++++++++++++---
  15  1 file changed, 51 insertions(+), 4 deletions(-)
  16
  17 --- a/drivers/gpio/gpio-realtek-otto.c
  18 +++ b/drivers/gpio/gpio-realtek-otto.c
  19 @@ -58,6 +58,8 @@ struct realtek_gpio_ctrl {
  20         raw_spinlock_t lock;
  21         u16 intr_mask[REALTEK_GPIO_PORTS_PER_BANK];
  22         u16 intr_type[REALTEK_GPIO_PORTS_PER_BANK];
  23 +       unsigned int (*port_offset_u8)(unsigned int port);
  24 +       unsigned int (*port_offset_u16)(unsigned int port);
  25  };
  26
  27  /* Expand with more flags as devices with other quirks are added */
  28 @@ -69,6 +71,11 @@ enum realtek_gpio_flags {
  29          * line the IRQ handler was assigned to, causing uncaught interrupts.
  30          */
  31         GPIO_INTERRUPTS_DISABLED = BIT(0),
  32 +       /*
  33 +        * Port order is reversed, meaning DCBA register layout for 1-bit
  34 +        * fields, and [BA, DC] for 2-bit fields.
  35 +        */
  36 +       GPIO_PORTS_REVERSED = BIT(1),
  37  };
  38
  39  static struct realtek_gpio_ctrl *irq_data_to_ctrl(struct irq_data *data)
  40 @@ -86,21 +93,50 @@ static struct realtek_gpio_ctrl *irq_dat
  41   * port. The two interrupt mask registers store two bits per GPIO, so use u16
  42   * values.
  43   */
  44 +static unsigned int realtek_gpio_port_offset_u8(unsigned int port)
  45 +{
  46 +       return port;
  47 +}
  48 +
  49 +static unsigned int realtek_gpio_port_offset_u16(unsigned int port)
  50 +{
  51 +       return 2 * port;
  52 +}
  53 +
  54 +/*
  55 + * Reversed port order register access
  56 + *
  57 + * For registers with one bit per GPIO, all ports are stored as u8-s in one
  58 + * register in reversed order. The two interrupt mask registers store two bits
  59 + * per GPIO, so use u16 values. The first register contains ports 1 and 0, the
  60 + * second ports 3 and 2.
  61 + */
  62 +static unsigned int realtek_gpio_port_offset_u8_rev(unsigned int port)
  63 +{
  64 +       return 3 - port;
  65 +}
  66 +
  67 +static unsigned int realtek_gpio_port_offset_u16_rev(unsigned int port)
  68 +{
  69 +       return 2 * (port ^ 1);
  70 +}
  71 +
  72  static void realtek_gpio_write_imr(struct realtek_gpio_ctrl *ctrl,
  73         unsigned int port, u16 irq_type, u16 irq_mask)
  74  {
  75 -       iowrite16(irq_type & irq_mask, ctrl->base + REALTEK_GPIO_REG_IMR + 2 * port);
  76 +       iowrite16(irq_type & irq_mask,
  77 +               ctrl->base + REALTEK_GPIO_REG_IMR + ctrl->port_offset_u16(port));
  78  }
  79
  80  static void realtek_gpio_clear_isr(struct realtek_gpio_ctrl *ctrl,
  81         unsigned int port, u8 mask)
  82  {
  83 -       iowrite8(mask, ctrl->base + REALTEK_GPIO_REG_ISR + port);
  84 +       iowrite8(mask, ctrl->base + REALTEK_GPIO_REG_ISR + ctrl->port_offset_u8(port));
  85  }
  86
  87  static u8 realtek_gpio_read_isr(struct realtek_gpio_ctrl *ctrl, unsigned int port)
  88  {
  89 -       return ioread8(ctrl->base + REALTEK_GPIO_REG_ISR + port);
  90 +       return ioread8(ctrl->base + REALTEK_GPIO_REG_ISR + ctrl->port_offset_u8(port));
  91  }
  92
  93  /* Set the rising and falling edge mask bits for a GPIO port pin */
  94 @@ -253,6 +289,7 @@ MODULE_DEVICE_TABLE(of, realtek_gpio_of_
  95  static int realtek_gpio_probe(struct platform_device *pdev)
  96  {
  97         struct device *dev = &pdev->dev;
  98 +       unsigned long bgpio_flags;
  99         unsigned int dev_flags;
 100         struct gpio_irq_chip *girq;
 101         struct realtek_gpio_ctrl *ctrl;
 102 @@ -280,10 +317,20 @@ static int realtek_gpio_probe(struct pla
 103
 104         raw_spin_lock_init(&ctrl->lock);
 105
 106 +       if (dev_flags & GPIO_PORTS_REVERSED) {
 107 +               bgpio_flags = 0;
 108 +               ctrl->port_offset_u8 = realtek_gpio_port_offset_u8_rev;
 109 +               ctrl->port_offset_u16 = realtek_gpio_port_offset_u16_rev;
 110 +       } else {
 111 +               bgpio_flags = BGPIOF_BIG_ENDIAN_BYTE_ORDER;
 112 +               ctrl->port_offset_u8 = realtek_gpio_port_offset_u8;
 113 +               ctrl->port_offset_u16 = realtek_gpio_port_offset_u16;
 114 +       }
 115 +
 116         err = bgpio_init(&ctrl->gc, dev, 4,
 117                 ctrl->base + REALTEK_GPIO_REG_DATA, NULL, NULL,
 118                 ctrl->base + REALTEK_GPIO_REG_DIR, NULL,
 119 -               BGPIOF_BIG_ENDIAN_BYTE_ORDER);
 120 +               bgpio_flags);
 121         if (err) {
 122                 dev_err(dev, "unable to init generic GPIO");
 123                 return err;