gpio: 104-dio-48e: Migrate to regmap API

The regmap API supports IO port accessors so we can take advantage of
regmap abstractions rather than handling access to the device registers
directly in the driver. The 104-dio-48e module is migrated to the new
i8255 library interface leveraging the gpio-regmap API.
Suggested-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: NAndy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: NWilliam Breathitt Gray <william.gray@linaro.org>
Signed-off-by: NBartosz Golaszewski <bartosz.golaszewski@linaro.org>

drivers/gpio/gpio-104-dio-48e.c

@@ -9,7 +9,6 @@
 #include <linux/bits.h>
 #include <linux/device.h>
 #include <linux/err.h>
-#include <linux/gpio/driver.h>
 #include <linux/ioport.h>
 #include <linux/irq.h>
 #include <linux/isa.h>
@@ -42,90 +41,6 @@ MODULE_PARM_DESC(irq, "ACCES 104-DIO-48E interrupt line numbers");
 
 #define DIO48E_NUM_PPI 2
 
-/**
- * struct dio48e_reg - device register structure
- * @ppi:		Programmable Peripheral Interface groups
- */
-struct dio48e_reg {
-	struct i8255 ppi[DIO48E_NUM_PPI];
-};
-
-/**
- * struct dio48e_gpio - GPIO device private data structure
- * @chip:		instance of the gpio_chip
- * @ppi_state:		PPI device states
- * @reg:		I/O address offset for the device registers
- */
-struct dio48e_gpio {
-	struct gpio_chip chip;
-	struct i8255_state ppi_state[DIO48E_NUM_PPI];
-	struct dio48e_reg __iomem *reg;
-};
-
-static int dio48e_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
-{
-	struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
-
-	if (i8255_get_direction(dio48egpio->ppi_state, offset))
-		return GPIO_LINE_DIRECTION_IN;
-
-	return GPIO_LINE_DIRECTION_OUT;
-}
-
-static int dio48e_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
-{
-	struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
-
-	i8255_direction_input(dio48egpio->reg->ppi, dio48egpio->ppi_state,
-			      offset);
-
-	return 0;
-}
-
-static int dio48e_gpio_direction_output(struct gpio_chip *chip, unsigned int offset,
-					int value)
-{
-	struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
-
-	i8255_direction_output(dio48egpio->reg->ppi, dio48egpio->ppi_state,
-			       offset, value);
-
-	return 0;
-}
-
-static int dio48e_gpio_get(struct gpio_chip *chip, unsigned int offset)
-{
-	struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
-
-	return i8255_get(dio48egpio->reg->ppi, offset);
-}
-
-static int dio48e_gpio_get_multiple(struct gpio_chip *chip, unsigned long *mask,
-	unsigned long *bits)
-{
-	struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
-
-	i8255_get_multiple(dio48egpio->reg->ppi, mask, bits, chip->ngpio);
-
-	return 0;
-}
-
-static void dio48e_gpio_set(struct gpio_chip *chip, unsigned int offset, int value)
-{
-	struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
-
-	i8255_set(dio48egpio->reg->ppi, dio48egpio->ppi_state, offset, value);
-}
-
-static void dio48e_gpio_set_multiple(struct gpio_chip *chip,
-	unsigned long *mask, unsigned long *bits)
-{
-	struct dio48e_gpio *const dio48egpio = gpiochip_get_data(chip);
-
-	i8255_set_multiple(dio48egpio->reg->ppi, dio48egpio->ppi_state, mask,
-			   bits, chip->ngpio);
-}
-
 static const struct regmap_range dio48e_wr_ranges[] = {
 	regmap_reg_range(0x0, 0x9), regmap_reg_range(0xB, 0xB),
 	regmap_reg_range(0xD, 0xD), regmap_reg_range(0xF, 0xF),
@@ -245,25 +160,10 @@ static int dio48e_irq_init_hw(struct regmap *const map)
 	return regmap_read(map, DIO48E_DISABLE_INTERRUPT, &val);
 }
 
-static void dio48e_init_ppi(struct i8255 __iomem *const ppi,
-			    struct i8255_state *const ppi_state)
-{
-	const unsigned long ngpio = 24;
-	const unsigned long mask = GENMASK(ngpio - 1, 0);
-	const unsigned long bits = 0;
-	unsigned long i;
-
-	/* Initialize all GPIO to output 0 */
-	for (i = 0; i < DIO48E_NUM_PPI; i++) {
-		i8255_mode0_output(&ppi[i]);
-		i8255_set_multiple(&ppi[i], &ppi_state[i], &mask, &bits, ngpio);
-	}
-}
-
 static int dio48e_probe(struct device *dev, unsigned int id)
 {
-	struct dio48e_gpio *dio48egpio;
 	const char *const name = dev_name(dev);
+	struct i8255_regmap_config config = {};
 	void __iomem *regs;
 	struct regmap *map;
 	int err;
@@ -271,10 +171,6 @@ static int dio48e_probe(struct device *dev, unsigned int id)
 	unsigned int irq_mask;
 	struct regmap_irq_chip_data *chip_data;
 
-	dio48egpio = devm_kzalloc(dev, sizeof(*dio48egpio), GFP_KERNEL);
-	if (!dio48egpio)
-		return -ENOMEM;
-
 	if (!devm_request_region(dev, base[id], DIO48E_EXTENT, name)) {
 		dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
 			base[id], base[id] + DIO48E_EXTENT);
@@ -284,7 +180,6 @@ static int dio48e_probe(struct device *dev, unsigned int id)
 	regs = devm_ioport_map(dev, base[id], DIO48E_EXTENT);
 	if (!regs)
 		return -ENOMEM;
-	dio48egpio->reg = regs;
 
 	map = devm_regmap_init_mmio(dev, regs, &dio48e_regmap_config);
 	if (IS_ERR(map))
@@ -321,31 +216,13 @@ static int dio48e_probe(struct device *dev, unsigned int id)
 	if (err)
 		return dev_err_probe(dev, err, "IRQ registration failed\n");
 
-	dio48egpio->chip.label = name;
-	dio48egpio->chip.parent = dev;
-	dio48egpio->chip.owner = THIS_MODULE;
-	dio48egpio->chip.base = -1;
-	dio48egpio->chip.ngpio = DIO48E_NGPIO;
-	dio48egpio->chip.names = dio48e_names;
-	dio48egpio->chip.get_direction = dio48e_gpio_get_direction;
-	dio48egpio->chip.direction_input = dio48e_gpio_direction_input;
-	dio48egpio->chip.direction_output = dio48e_gpio_direction_output;
-	dio48egpio->chip.get = dio48e_gpio_get;
-	dio48egpio->chip.get_multiple = dio48e_gpio_get_multiple;
-	dio48egpio->chip.set = dio48e_gpio_set;
-	dio48egpio->chip.set_multiple = dio48e_gpio_set_multiple;
-
-	i8255_state_init(dio48egpio->ppi_state, DIO48E_NUM_PPI);
-	dio48e_init_ppi(dio48egpio->reg->ppi, dio48egpio->ppi_state);
-
-	err = devm_gpiochip_add_data(dev, &dio48egpio->chip, dio48egpio);
-	if (err) {
-		dev_err(dev, "GPIO registering failed (%d)\n", err);
-		return err;
-	}
+	config.parent = dev;
+	config.map = map;
+	config.num_ppi = DIO48E_NUM_PPI;
+	config.names = dio48e_names;
+	config.domain = regmap_irq_get_domain(chip_data);
 
-	return gpiochip_irqchip_add_domain(&dio48egpio->chip,
-					   regmap_irq_get_domain(chip_data));
+	return devm_i8255_regmap_register(dev, &config);
 }
 
 static struct isa_driver dio48e_driver = {