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v6.8
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * GPIO driver for the WinSystems WS16C48
  4 * Copyright (C) 2016 William Breathitt Gray
  5 */
  6#include <linux/bitfield.h>
  7#include <linux/bits.h>
  8#include <linux/device.h>
  9#include <linux/err.h>
 10#include <linux/gpio/regmap.h>
 11#include <linux/irq.h>
 
 
 
 12#include <linux/isa.h>
 13#include <linux/kernel.h>
 14#include <linux/module.h>
 15#include <linux/moduleparam.h>
 16#include <linux/spinlock.h>
 17#include <linux/regmap.h>
 18#include <linux/types.h>
 19
 20#define WS16C48_EXTENT 11
 21#define MAX_NUM_WS16C48 max_num_isa_dev(WS16C48_EXTENT)
 22
 23static unsigned int base[MAX_NUM_WS16C48];
 24static unsigned int num_ws16c48;
 25module_param_hw_array(base, uint, ioport, &num_ws16c48, 0);
 26MODULE_PARM_DESC(base, "WinSystems WS16C48 base addresses");
 27
 28static unsigned int irq[MAX_NUM_WS16C48];
 29static unsigned int num_irq;
 30module_param_hw_array(irq, uint, irq, &num_irq, 0);
 31MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers");
 32
 33#define WS16C48_DAT_BASE 0x0
 34#define WS16C48_PAGE_LOCK 0x7
 35#define WS16C48_PAGE_BASE 0x8
 36#define WS16C48_POL WS16C48_PAGE_BASE
 37#define WS16C48_ENAB WS16C48_PAGE_BASE
 38#define WS16C48_INT_ID WS16C48_PAGE_BASE
 39
 40#define PAGE_LOCK_PAGE_FIELD GENMASK(7, 6)
 41#define POL_PAGE u8_encode_bits(1, PAGE_LOCK_PAGE_FIELD)
 42#define ENAB_PAGE u8_encode_bits(2, PAGE_LOCK_PAGE_FIELD)
 43#define INT_ID_PAGE u8_encode_bits(3, PAGE_LOCK_PAGE_FIELD)
 44
 45static const struct regmap_range ws16c48_wr_ranges[] = {
 46	regmap_reg_range(0x0, 0x5), regmap_reg_range(0x7, 0xA),
 47};
 48static const struct regmap_range ws16c48_rd_ranges[] = {
 49	regmap_reg_range(0x0, 0xA),
 50};
 51static const struct regmap_range ws16c48_volatile_ranges[] = {
 52	regmap_reg_range(0x0, 0x6), regmap_reg_range(0x8, 0xA),
 53};
 54static const struct regmap_access_table ws16c48_wr_table = {
 55	.yes_ranges = ws16c48_wr_ranges,
 56	.n_yes_ranges = ARRAY_SIZE(ws16c48_wr_ranges),
 57};
 58static const struct regmap_access_table ws16c48_rd_table = {
 59	.yes_ranges = ws16c48_rd_ranges,
 60	.n_yes_ranges = ARRAY_SIZE(ws16c48_rd_ranges),
 61};
 62static const struct regmap_access_table ws16c48_volatile_table = {
 63	.yes_ranges = ws16c48_volatile_ranges,
 64	.n_yes_ranges = ARRAY_SIZE(ws16c48_volatile_ranges),
 65};
 66static const struct regmap_config ws16c48_regmap_config = {
 67	.reg_bits = 8,
 68	.reg_stride = 1,
 69	.val_bits = 8,
 70	.io_port = true,
 71	.wr_table = &ws16c48_wr_table,
 72	.rd_table = &ws16c48_rd_table,
 73	.volatile_table = &ws16c48_volatile_table,
 74	.cache_type = REGCACHE_FLAT,
 75	.use_raw_spinlock = true,
 76};
 77
 78#define WS16C48_NGPIO_PER_REG 8
 79#define WS16C48_REGMAP_IRQ(_id)							\
 80	[_id] = {								\
 81		.reg_offset = (_id) / WS16C48_NGPIO_PER_REG,			\
 82		.mask = BIT((_id) % WS16C48_NGPIO_PER_REG),			\
 83		.type = {							\
 84			.type_reg_offset = (_id) / WS16C48_NGPIO_PER_REG,	\
 85			.types_supported = IRQ_TYPE_EDGE_BOTH,			\
 86		},								\
 87	}
 88
 89/* Only the first 24 lines (Port 0-2) support interrupts */
 90#define WS16C48_NUM_IRQS 24
 91static const struct regmap_irq ws16c48_regmap_irqs[WS16C48_NUM_IRQS] = {
 92	WS16C48_REGMAP_IRQ(0), WS16C48_REGMAP_IRQ(1), WS16C48_REGMAP_IRQ(2), /* 0-2 */
 93	WS16C48_REGMAP_IRQ(3), WS16C48_REGMAP_IRQ(4), WS16C48_REGMAP_IRQ(5), /* 3-5 */
 94	WS16C48_REGMAP_IRQ(6), WS16C48_REGMAP_IRQ(7), WS16C48_REGMAP_IRQ(8), /* 6-8 */
 95	WS16C48_REGMAP_IRQ(9), WS16C48_REGMAP_IRQ(10), WS16C48_REGMAP_IRQ(11), /* 9-11 */
 96	WS16C48_REGMAP_IRQ(12), WS16C48_REGMAP_IRQ(13), WS16C48_REGMAP_IRQ(14), /* 12-14 */
 97	WS16C48_REGMAP_IRQ(15), WS16C48_REGMAP_IRQ(16), WS16C48_REGMAP_IRQ(17), /* 15-17 */
 98	WS16C48_REGMAP_IRQ(18), WS16C48_REGMAP_IRQ(19), WS16C48_REGMAP_IRQ(20), /* 18-20 */
 99	WS16C48_REGMAP_IRQ(21), WS16C48_REGMAP_IRQ(22), WS16C48_REGMAP_IRQ(23), /* 21-23 */
100};
101
102/**
103 * struct ws16c48_gpio - GPIO device private data structure
104 * @map:	regmap for the device
 
 
105 * @lock:	synchronization lock to prevent I/O race conditions
106 * @irq_mask:	I/O bits affected by interrupts
 
 
107 */
108struct ws16c48_gpio {
109	struct regmap *map;
 
 
110	raw_spinlock_t lock;
111	u8 irq_mask[WS16C48_NUM_IRQS / WS16C48_NGPIO_PER_REG];
 
 
112};
113
114static int ws16c48_handle_pre_irq(void *const irq_drv_data) __acquires(&ws16c48gpio->lock)
 
 
 
 
 
 
 
 
 
115{
116	struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
 
 
 
 
 
117
118	/* Lock to prevent Page/Lock register change while we handle IRQ */
119	raw_spin_lock(&ws16c48gpio->lock);
 
 
 
120
121	return 0;
122}
123
124static int ws16c48_handle_post_irq(void *const irq_drv_data) __releases(&ws16c48gpio->lock)
 
125{
126	struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
 
 
 
 
 
 
 
 
 
 
 
 
127
128	raw_spin_unlock(&ws16c48gpio->lock);
129
130	return 0;
131}
132
133static int ws16c48_handle_mask_sync(const int index, const unsigned int mask_buf_def,
134				    const unsigned int mask_buf, void *const irq_drv_data)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
135{
136	struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
 
 
 
 
137	unsigned long flags;
138	int ret = 0;
 
 
 
139
140	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
141
142	/* exit early if no change since the last mask sync */
143	if (mask_buf == ws16c48gpio->irq_mask[index])
144		goto exit_unlock;
145	ws16c48gpio->irq_mask[index] = mask_buf;
146
147	ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, ENAB_PAGE);
148	if (ret)
149		goto exit_unlock;
150
151	/* Update ENAB register (inverted mask) */
152	ret = regmap_write(ws16c48gpio->map, WS16C48_ENAB + index, ~mask_buf);
153	if (ret)
154		goto exit_unlock;
155
156	ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, INT_ID_PAGE);
157	if (ret)
158		goto exit_unlock;
159
160exit_unlock:
161	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
 
162
163	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
164}
165
166static int ws16c48_set_type_config(unsigned int **const buf, const unsigned int type,
167				   const struct regmap_irq *const irq_data, const int idx,
168				   void *const irq_drv_data)
169{
170	struct ws16c48_gpio *const ws16c48gpio = irq_drv_data;
171	unsigned int polarity;
 
 
 
172	unsigned long flags;
173	int ret;
174
175	switch (type) {
 
 
 
 
 
 
 
 
176	case IRQ_TYPE_EDGE_RISING:
177		polarity = irq_data->mask;
178		break;
179	case IRQ_TYPE_EDGE_FALLING:
180		polarity = 0;
181		break;
182	default:
 
183		return -EINVAL;
184	}
185
186	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
187
188	ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, POL_PAGE);
189	if (ret)
190		goto exit_unlock;
191
192	/* Set interrupt polarity */
193	ret = regmap_update_bits(ws16c48gpio->map, WS16C48_POL + idx, irq_data->mask, polarity);
194	if (ret)
195		goto exit_unlock;
196
197	ret = regmap_write(ws16c48gpio->map, WS16C48_PAGE_LOCK, INT_ID_PAGE);
198	if (ret)
199		goto exit_unlock;
200
201exit_unlock:
202	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
203
204	return ret;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
205}
206
207#define WS16C48_NGPIO 48
208static const char *ws16c48_names[WS16C48_NGPIO] = {
209	"Port 0 Bit 0", "Port 0 Bit 1", "Port 0 Bit 2", "Port 0 Bit 3",
210	"Port 0 Bit 4", "Port 0 Bit 5", "Port 0 Bit 6", "Port 0 Bit 7",
211	"Port 1 Bit 0", "Port 1 Bit 1", "Port 1 Bit 2", "Port 1 Bit 3",
212	"Port 1 Bit 4", "Port 1 Bit 5", "Port 1 Bit 6", "Port 1 Bit 7",
213	"Port 2 Bit 0", "Port 2 Bit 1", "Port 2 Bit 2", "Port 2 Bit 3",
214	"Port 2 Bit 4", "Port 2 Bit 5", "Port 2 Bit 6", "Port 2 Bit 7",
215	"Port 3 Bit 0", "Port 3 Bit 1", "Port 3 Bit 2", "Port 3 Bit 3",
216	"Port 3 Bit 4", "Port 3 Bit 5", "Port 3 Bit 6", "Port 3 Bit 7",
217	"Port 4 Bit 0", "Port 4 Bit 1", "Port 4 Bit 2", "Port 4 Bit 3",
218	"Port 4 Bit 4", "Port 4 Bit 5", "Port 4 Bit 6", "Port 4 Bit 7",
219	"Port 5 Bit 0", "Port 5 Bit 1", "Port 5 Bit 2", "Port 5 Bit 3",
220	"Port 5 Bit 4", "Port 5 Bit 5", "Port 5 Bit 6", "Port 5 Bit 7"
221};
222
223static int ws16c48_irq_init_hw(struct regmap *const map)
224{
225	int err;
226
227	err = regmap_write(map, WS16C48_PAGE_LOCK, ENAB_PAGE);
228	if (err)
229		return err;
230
231	/* Disable interrupts for all lines */
232	err = regmap_write(map, WS16C48_ENAB + 0, 0x00);
233	if (err)
234		return err;
235	err = regmap_write(map, WS16C48_ENAB + 1, 0x00);
236	if (err)
237		return err;
238	err = regmap_write(map, WS16C48_ENAB + 2, 0x00);
239	if (err)
240		return err;
241
242	return regmap_write(map, WS16C48_PAGE_LOCK, INT_ID_PAGE);
243}
244
245static int ws16c48_probe(struct device *dev, unsigned int id)
246{
247	struct ws16c48_gpio *ws16c48gpio;
248	const char *const name = dev_name(dev);
249	int err;
250	struct gpio_regmap_config gpio_config = {};
251	void __iomem *regs;
252	struct regmap_irq_chip *chip;
253	struct regmap_irq_chip_data *chip_data;
254
255	ws16c48gpio = devm_kzalloc(dev, sizeof(*ws16c48gpio), GFP_KERNEL);
256	if (!ws16c48gpio)
257		return -ENOMEM;
258
259	if (!devm_request_region(dev, base[id], WS16C48_EXTENT, name)) {
260		dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
261			base[id], base[id] + WS16C48_EXTENT);
262		return -EBUSY;
263	}
264
265	regs = devm_ioport_map(dev, base[id], WS16C48_EXTENT);
266	if (!regs)
267		return -ENOMEM;
268
269	ws16c48gpio->map = devm_regmap_init_mmio(dev, regs, &ws16c48_regmap_config);
270	if (IS_ERR(ws16c48gpio->map))
271		return dev_err_probe(dev, PTR_ERR(ws16c48gpio->map),
272				     "Unable to initialize register map\n");
273
274	chip = devm_kzalloc(dev, sizeof(*chip), GFP_KERNEL);
275	if (!chip)
276		return -ENOMEM;
277
278	chip->name = name;
279	chip->status_base = WS16C48_INT_ID;
280	chip->mask_base = WS16C48_ENAB;
281	chip->ack_base = WS16C48_INT_ID;
282	chip->num_regs = 3;
283	chip->irqs = ws16c48_regmap_irqs;
284	chip->num_irqs = ARRAY_SIZE(ws16c48_regmap_irqs);
285	chip->handle_pre_irq = ws16c48_handle_pre_irq;
286	chip->handle_post_irq = ws16c48_handle_post_irq;
287	chip->handle_mask_sync = ws16c48_handle_mask_sync;
288	chip->set_type_config = ws16c48_set_type_config;
289	chip->irq_drv_data = ws16c48gpio;
290
291	raw_spin_lock_init(&ws16c48gpio->lock);
292
293	/* Initialize to prevent spurious interrupts before we're ready */
294	err = ws16c48_irq_init_hw(ws16c48gpio->map);
295	if (err)
296		return err;
 
297
298	err = devm_regmap_add_irq_chip(dev, ws16c48gpio->map, irq[id], 0, 0, chip, &chip_data);
299	if (err)
300		return dev_err_probe(dev, err, "IRQ registration failed\n");
301
302	gpio_config.parent = dev;
303	gpio_config.regmap = ws16c48gpio->map;
304	gpio_config.ngpio = WS16C48_NGPIO;
305	gpio_config.names = ws16c48_names;
306	gpio_config.reg_dat_base = GPIO_REGMAP_ADDR(WS16C48_DAT_BASE);
307	gpio_config.reg_set_base = GPIO_REGMAP_ADDR(WS16C48_DAT_BASE);
308	/* Setting a GPIO to 0 allows it to be used as an input */
309	gpio_config.reg_dir_out_base = GPIO_REGMAP_ADDR(WS16C48_DAT_BASE);
310	gpio_config.ngpio_per_reg = WS16C48_NGPIO_PER_REG;
311	gpio_config.irq_domain = regmap_irq_get_domain(chip_data);
312
313	return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &gpio_config));
 
 
 
 
 
 
 
314}
315
316static struct isa_driver ws16c48_driver = {
317	.probe = ws16c48_probe,
318	.driver = {
319		.name = "ws16c48"
320	},
321};
322
323module_isa_driver_with_irq(ws16c48_driver, num_ws16c48, num_irq);
324
325MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
326MODULE_DESCRIPTION("WinSystems WS16C48 GPIO driver");
327MODULE_LICENSE("GPL v2");
v5.4
  1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * GPIO driver for the WinSystems WS16C48
  4 * Copyright (C) 2016 William Breathitt Gray
  5 */
  6#include <linux/bitmap.h>
  7#include <linux/bitops.h>
  8#include <linux/device.h>
  9#include <linux/errno.h>
 10#include <linux/gpio/driver.h>
 11#include <linux/io.h>
 12#include <linux/ioport.h>
 13#include <linux/interrupt.h>
 14#include <linux/irqdesc.h>
 15#include <linux/isa.h>
 16#include <linux/kernel.h>
 17#include <linux/module.h>
 18#include <linux/moduleparam.h>
 19#include <linux/spinlock.h>
 
 
 20
 21#define WS16C48_EXTENT 16
 22#define MAX_NUM_WS16C48 max_num_isa_dev(WS16C48_EXTENT)
 23
 24static unsigned int base[MAX_NUM_WS16C48];
 25static unsigned int num_ws16c48;
 26module_param_hw_array(base, uint, ioport, &num_ws16c48, 0);
 27MODULE_PARM_DESC(base, "WinSystems WS16C48 base addresses");
 28
 29static unsigned int irq[MAX_NUM_WS16C48];
 30module_param_hw_array(irq, uint, irq, NULL, 0);
 
 31MODULE_PARM_DESC(irq, "WinSystems WS16C48 interrupt line numbers");
 32
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 33/**
 34 * struct ws16c48_gpio - GPIO device private data structure
 35 * @chip:	instance of the gpio_chip
 36 * @io_state:	bit I/O state (whether bit is set to input or output)
 37 * @out_state:	output bits state
 38 * @lock:	synchronization lock to prevent I/O race conditions
 39 * @irq_mask:	I/O bits affected by interrupts
 40 * @flow_mask:	IRQ flow type mask for the respective I/O bits
 41 * @base:	base port address of the GPIO device
 42 */
 43struct ws16c48_gpio {
 44	struct gpio_chip chip;
 45	unsigned char io_state[6];
 46	unsigned char out_state[6];
 47	raw_spinlock_t lock;
 48	unsigned long irq_mask;
 49	unsigned long flow_mask;
 50	unsigned base;
 51};
 52
 53static int ws16c48_gpio_get_direction(struct gpio_chip *chip, unsigned offset)
 54{
 55	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
 56	const unsigned port = offset / 8;
 57	const unsigned mask = BIT(offset % 8);
 58
 59	return !!(ws16c48gpio->io_state[port] & mask);
 60}
 61
 62static int ws16c48_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
 63{
 64	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
 65	const unsigned port = offset / 8;
 66	const unsigned mask = BIT(offset % 8);
 67	unsigned long flags;
 68
 69	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
 70
 71	ws16c48gpio->io_state[port] |= mask;
 72	ws16c48gpio->out_state[port] &= ~mask;
 73	outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
 74
 75	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
 76
 77	return 0;
 78}
 79
 80static int ws16c48_gpio_direction_output(struct gpio_chip *chip,
 81	unsigned offset, int value)
 82{
 83	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
 84	const unsigned port = offset / 8;
 85	const unsigned mask = BIT(offset % 8);
 86	unsigned long flags;
 87
 88	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
 89
 90	ws16c48gpio->io_state[port] &= ~mask;
 91	if (value)
 92		ws16c48gpio->out_state[port] |= mask;
 93	else
 94		ws16c48gpio->out_state[port] &= ~mask;
 95	outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
 96
 97	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
 98
 99	return 0;
100}
101
102static int ws16c48_gpio_get(struct gpio_chip *chip, unsigned offset)
103{
104	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
105	const unsigned port = offset / 8;
106	const unsigned mask = BIT(offset % 8);
107	unsigned long flags;
108	unsigned port_state;
109
110	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
111
112	/* ensure that GPIO is set for input */
113	if (!(ws16c48gpio->io_state[port] & mask)) {
114		raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
115		return -EINVAL;
116	}
117
118	port_state = inb(ws16c48gpio->base + port);
119
120	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
121
122	return !!(port_state & mask);
123}
124
125static int ws16c48_gpio_get_multiple(struct gpio_chip *chip,
126	unsigned long *mask, unsigned long *bits)
127{
128	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
129	const unsigned int gpio_reg_size = 8;
130	size_t i;
131	const size_t num_ports = chip->ngpio / gpio_reg_size;
132	unsigned int bits_offset;
133	size_t word_index;
134	unsigned int word_offset;
135	unsigned long word_mask;
136	const unsigned long port_mask = GENMASK(gpio_reg_size - 1, 0);
137	unsigned long port_state;
138
139	/* clear bits array to a clean slate */
140	bitmap_zero(bits, chip->ngpio);
141
142	/* get bits are evaluated a gpio port register at a time */
143	for (i = 0; i < num_ports; i++) {
144		/* gpio offset in bits array */
145		bits_offset = i * gpio_reg_size;
146
147		/* word index for bits array */
148		word_index = BIT_WORD(bits_offset);
149
150		/* gpio offset within current word of bits array */
151		word_offset = bits_offset % BITS_PER_LONG;
152
153		/* mask of get bits for current gpio within current word */
154		word_mask = mask[word_index] & (port_mask << word_offset);
155		if (!word_mask) {
156			/* no get bits in this port so skip to next one */
157			continue;
158		}
159
160		/* read bits from current gpio port */
161		port_state = inb(ws16c48gpio->base + i);
162
163		/* store acquired bits at respective bits array offset */
164		bits[word_index] |= (port_state << word_offset) & word_mask;
165	}
166
167	return 0;
168}
169
170static void ws16c48_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
171{
172	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
173	const unsigned port = offset / 8;
174	const unsigned mask = BIT(offset % 8);
175	unsigned long flags;
176
177	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
178
179	/* ensure that GPIO is set for output */
180	if (ws16c48gpio->io_state[port] & mask) {
181		raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
182		return;
183	}
184
185	if (value)
186		ws16c48gpio->out_state[port] |= mask;
187	else
188		ws16c48gpio->out_state[port] &= ~mask;
189	outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
190
191	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
192}
193
194static void ws16c48_gpio_set_multiple(struct gpio_chip *chip,
195	unsigned long *mask, unsigned long *bits)
196{
197	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
198	unsigned int i;
199	const unsigned int gpio_reg_size = 8;
200	unsigned int port;
201	unsigned int iomask;
202	unsigned int bitmask;
203	unsigned long flags;
204
205	/* set bits are evaluated a gpio register size at a time */
206	for (i = 0; i < chip->ngpio; i += gpio_reg_size) {
207		/* no more set bits in this mask word; skip to the next word */
208		if (!mask[BIT_WORD(i)]) {
209			i = (BIT_WORD(i) + 1) * BITS_PER_LONG - gpio_reg_size;
210			continue;
211		}
212
213		port = i / gpio_reg_size;
214
215		/* mask out GPIO configured for input */
216		iomask = mask[BIT_WORD(i)] & ~ws16c48gpio->io_state[port];
217		bitmask = iomask & bits[BIT_WORD(i)];
218
219		raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
220
221		/* update output state data and set device gpio register */
222		ws16c48gpio->out_state[port] &= ~iomask;
223		ws16c48gpio->out_state[port] |= bitmask;
224		outb(ws16c48gpio->out_state[port], ws16c48gpio->base + port);
225
226		raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
227
228		/* prepare for next gpio register set */
229		mask[BIT_WORD(i)] >>= gpio_reg_size;
230		bits[BIT_WORD(i)] >>= gpio_reg_size;
231	}
232}
233
234static void ws16c48_irq_ack(struct irq_data *data)
235{
236	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
237	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
238	const unsigned long offset = irqd_to_hwirq(data);
239	const unsigned port = offset / 8;
240	const unsigned mask = BIT(offset % 8);
241	unsigned long flags;
242	unsigned port_state;
243
244	/* only the first 3 ports support interrupts */
245	if (port > 2)
246		return;
247
248	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
249
250	port_state = ws16c48gpio->irq_mask >> (8*port);
251
252	outb(0x80, ws16c48gpio->base + 7);
253	outb(port_state & ~mask, ws16c48gpio->base + 8 + port);
254	outb(port_state | mask, ws16c48gpio->base + 8 + port);
255	outb(0xC0, ws16c48gpio->base + 7);
256
257	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
258}
259
260static void ws16c48_irq_mask(struct irq_data *data)
261{
262	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
263	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
264	const unsigned long offset = irqd_to_hwirq(data);
265	const unsigned long mask = BIT(offset);
266	const unsigned port = offset / 8;
267	unsigned long flags;
268
269	/* only the first 3 ports support interrupts */
270	if (port > 2)
271		return;
272
273	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
274
275	ws16c48gpio->irq_mask &= ~mask;
276
277	outb(0x80, ws16c48gpio->base + 7);
278	outb(ws16c48gpio->irq_mask >> (8*port), ws16c48gpio->base + 8 + port);
279	outb(0xC0, ws16c48gpio->base + 7);
 
 
 
 
 
 
 
 
 
 
 
 
280
 
281	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
282}
283
284static void ws16c48_irq_unmask(struct irq_data *data)
285{
286	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
287	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
288	const unsigned long offset = irqd_to_hwirq(data);
289	const unsigned long mask = BIT(offset);
290	const unsigned port = offset / 8;
291	unsigned long flags;
292
293	/* only the first 3 ports support interrupts */
294	if (port > 2)
295		return;
296
297	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
298
299	ws16c48gpio->irq_mask |= mask;
300
301	outb(0x80, ws16c48gpio->base + 7);
302	outb(ws16c48gpio->irq_mask >> (8*port), ws16c48gpio->base + 8 + port);
303	outb(0xC0, ws16c48gpio->base + 7);
304
305	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
306}
307
308static int ws16c48_irq_set_type(struct irq_data *data, unsigned flow_type)
 
 
309{
310	struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
311	struct ws16c48_gpio *const ws16c48gpio = gpiochip_get_data(chip);
312	const unsigned long offset = irqd_to_hwirq(data);
313	const unsigned long mask = BIT(offset);
314	const unsigned port = offset / 8;
315	unsigned long flags;
 
316
317	/* only the first 3 ports support interrupts */
318	if (port > 2)
319		return -EINVAL;
320
321	raw_spin_lock_irqsave(&ws16c48gpio->lock, flags);
322
323	switch (flow_type) {
324	case IRQ_TYPE_NONE:
325		break;
326	case IRQ_TYPE_EDGE_RISING:
327		ws16c48gpio->flow_mask |= mask;
328		break;
329	case IRQ_TYPE_EDGE_FALLING:
330		ws16c48gpio->flow_mask &= ~mask;
331		break;
332	default:
333		raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
334		return -EINVAL;
335	}
336
337	outb(0x40, ws16c48gpio->base + 7);
338	outb(ws16c48gpio->flow_mask >> (8*port), ws16c48gpio->base + 8 + port);
339	outb(0xC0, ws16c48gpio->base + 7);
 
 
 
 
 
 
 
 
 
 
 
340
 
341	raw_spin_unlock_irqrestore(&ws16c48gpio->lock, flags);
342
343	return 0;
344}
345
346static struct irq_chip ws16c48_irqchip = {
347	.name = "ws16c48",
348	.irq_ack = ws16c48_irq_ack,
349	.irq_mask = ws16c48_irq_mask,
350	.irq_unmask = ws16c48_irq_unmask,
351	.irq_set_type = ws16c48_irq_set_type
352};
353
354static irqreturn_t ws16c48_irq_handler(int irq, void *dev_id)
355{
356	struct ws16c48_gpio *const ws16c48gpio = dev_id;
357	struct gpio_chip *const chip = &ws16c48gpio->chip;
358	unsigned long int_pending;
359	unsigned long port;
360	unsigned long int_id;
361	unsigned long gpio;
362
363	int_pending = inb(ws16c48gpio->base + 6) & 0x7;
364	if (!int_pending)
365		return IRQ_NONE;
366
367	/* loop until all pending interrupts are handled */
368	do {
369		for_each_set_bit(port, &int_pending, 3) {
370			int_id = inb(ws16c48gpio->base + 8 + port);
371			for_each_set_bit(gpio, &int_id, 8)
372				generic_handle_irq(irq_find_mapping(
373					chip->irq.domain, gpio + 8*port));
374		}
375
376		int_pending = inb(ws16c48gpio->base + 6) & 0x7;
377	} while (int_pending);
378
379	return IRQ_HANDLED;
380}
381
382#define WS16C48_NGPIO 48
383static const char *ws16c48_names[WS16C48_NGPIO] = {
384	"Port 0 Bit 0", "Port 0 Bit 1", "Port 0 Bit 2", "Port 0 Bit 3",
385	"Port 0 Bit 4", "Port 0 Bit 5", "Port 0 Bit 6", "Port 0 Bit 7",
386	"Port 1 Bit 0", "Port 1 Bit 1", "Port 1 Bit 2", "Port 1 Bit 3",
387	"Port 1 Bit 4", "Port 1 Bit 5", "Port 1 Bit 6", "Port 1 Bit 7",
388	"Port 2 Bit 0", "Port 2 Bit 1", "Port 2 Bit 2", "Port 2 Bit 3",
389	"Port 2 Bit 4", "Port 2 Bit 5", "Port 2 Bit 6", "Port 2 Bit 7",
390	"Port 3 Bit 0", "Port 3 Bit 1", "Port 3 Bit 2", "Port 3 Bit 3",
391	"Port 3 Bit 4", "Port 3 Bit 5", "Port 3 Bit 6", "Port 3 Bit 7",
392	"Port 4 Bit 0", "Port 4 Bit 1", "Port 4 Bit 2", "Port 4 Bit 3",
393	"Port 4 Bit 4", "Port 4 Bit 5", "Port 4 Bit 6", "Port 4 Bit 7",
394	"Port 5 Bit 0", "Port 5 Bit 1", "Port 5 Bit 2", "Port 5 Bit 3",
395	"Port 5 Bit 4", "Port 5 Bit 5", "Port 5 Bit 6", "Port 5 Bit 7"
396};
397
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
398static int ws16c48_probe(struct device *dev, unsigned int id)
399{
400	struct ws16c48_gpio *ws16c48gpio;
401	const char *const name = dev_name(dev);
402	int err;
 
 
 
 
403
404	ws16c48gpio = devm_kzalloc(dev, sizeof(*ws16c48gpio), GFP_KERNEL);
405	if (!ws16c48gpio)
406		return -ENOMEM;
407
408	if (!devm_request_region(dev, base[id], WS16C48_EXTENT, name)) {
409		dev_err(dev, "Unable to lock port addresses (0x%X-0x%X)\n",
410			base[id], base[id] + WS16C48_EXTENT);
411		return -EBUSY;
412	}
413
414	ws16c48gpio->chip.label = name;
415	ws16c48gpio->chip.parent = dev;
416	ws16c48gpio->chip.owner = THIS_MODULE;
417	ws16c48gpio->chip.base = -1;
418	ws16c48gpio->chip.ngpio = WS16C48_NGPIO;
419	ws16c48gpio->chip.names = ws16c48_names;
420	ws16c48gpio->chip.get_direction = ws16c48_gpio_get_direction;
421	ws16c48gpio->chip.direction_input = ws16c48_gpio_direction_input;
422	ws16c48gpio->chip.direction_output = ws16c48_gpio_direction_output;
423	ws16c48gpio->chip.get = ws16c48_gpio_get;
424	ws16c48gpio->chip.get_multiple = ws16c48_gpio_get_multiple;
425	ws16c48gpio->chip.set = ws16c48_gpio_set;
426	ws16c48gpio->chip.set_multiple = ws16c48_gpio_set_multiple;
427	ws16c48gpio->base = base[id];
 
 
 
 
 
 
 
 
 
 
 
428
429	raw_spin_lock_init(&ws16c48gpio->lock);
430
431	err = devm_gpiochip_add_data(dev, &ws16c48gpio->chip, ws16c48gpio);
432	if (err) {
433		dev_err(dev, "GPIO registering failed (%d)\n", err);
434		return err;
435	}
436
437	/* Disable IRQ by default */
438	outb(0x80, base[id] + 7);
439	outb(0, base[id] + 8);
440	outb(0, base[id] + 9);
441	outb(0, base[id] + 10);
442	outb(0xC0, base[id] + 7);
443
444	err = gpiochip_irqchip_add(&ws16c48gpio->chip, &ws16c48_irqchip, 0,
445		handle_edge_irq, IRQ_TYPE_NONE);
446	if (err) {
447		dev_err(dev, "Could not add irqchip (%d)\n", err);
448		return err;
449	}
 
450
451	err = devm_request_irq(dev, irq[id], ws16c48_irq_handler, IRQF_SHARED,
452		name, ws16c48gpio);
453	if (err) {
454		dev_err(dev, "IRQ handler registering failed (%d)\n", err);
455		return err;
456	}
457
458	return 0;
459}
460
461static struct isa_driver ws16c48_driver = {
462	.probe = ws16c48_probe,
463	.driver = {
464		.name = "ws16c48"
465	},
466};
467
468module_isa_driver(ws16c48_driver, num_ws16c48);
469
470MODULE_AUTHOR("William Breathitt Gray <vilhelm.gray@gmail.com>");
471MODULE_DESCRIPTION("WinSystems WS16C48 GPIO driver");
472MODULE_LICENSE("GPL v2");