// SPDX-License-Identifier: GPL-2.0
/*
* Digital I/O driver for Technologic Systems TS-5500
*
* Copyright (c) 2012 Savoir-faire Linux Inc.
* Vivien Didelot <vivien.didelot@savoirfairelinux.com>
*
* Technologic Systems platforms have pin blocks, exposing several Digital
* Input/Output lines (DIO). This driver aims to support single pin blocks.
* In that sense, the support is not limited to the TS-5500 blocks.
* Actually, the following platforms have DIO support:
*
* TS-5500:
* Documentation: http://wiki.embeddedarm.com/wiki/TS-5500
* Blocks: DIO1, DIO2 and LCD port.
*
* TS-5600:
* Documentation: http://wiki.embeddedarm.com/wiki/TS-5600
* Blocks: LCD port (identical to TS-5500 LCD).
*/
#include <linux/bitops.h>
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
/* List of supported Technologic Systems platforms DIO blocks */
enum ts5500_blocks { TS5500_DIO1, TS5500_DIO2, TS5500_LCD, TS5600_LCD };
struct ts5500_priv {
const struct ts5500_dio *pinout;
struct gpio_chip gpio_chip;
spinlock_t lock;
bool strap;
u8 hwirq;
};
/*
* Hex 7D is used to control several blocks (e.g. DIO2 and LCD port).
* This flag ensures that the region has been requested by this driver.
*/
static bool hex7d_reserved;
/*
* This structure is used to describe capabilities of DIO lines,
* such as available directions and connected interrupt (if any).
*/
struct ts5500_dio {
const u8 value_addr;
const u8 value_mask;
const u8 control_addr;
const u8 control_mask;
const bool no_input;
const bool no_output;
const u8 irq;
};
#define TS5500_DIO_IN_OUT(vaddr, vbit, caddr, cbit) \
{ \
.value_addr = vaddr, \
.value_mask = BIT(vbit), \
.control_addr = caddr, \
.control_mask = BIT(cbit), \
}
#define TS5500_DIO_IN(addr, bit) \
{ \
.value_addr = addr, \
.value_mask = BIT(bit), \
.no_output = true, \
}
#define TS5500_DIO_IN_IRQ(addr, bit, _irq) \
{ \
.value_addr = addr, \
.value_mask = BIT(bit), \
.no_output = true, \
.irq = _irq, \
}
#define TS5500_DIO_OUT(addr, bit) \
{ \
.value_addr = addr, \
.value_mask = BIT(bit), \
.no_input = true, \
}
/*
* Input/Output DIO lines are programmed in groups of 4. Their values are
* available through 4 consecutive bits in a value port, whereas the direction
* of these 4 lines is driven by only 1 bit in a control port.
*/
#define TS5500_DIO_GROUP(vaddr, vbitfrom, caddr, cbit) \
TS5500_DIO_IN_OUT(vaddr, vbitfrom + 0, caddr, cbit), \
TS5500_DIO_IN_OUT(vaddr, vbitfrom + 1, caddr, cbit), \
TS5500_DIO_IN_OUT(vaddr, vbitfrom + 2, caddr, cbit), \
TS5500_DIO_IN_OUT(vaddr, vbitfrom + 3, caddr, cbit)
/*
* TS-5500 DIO1 block
*
* value control dir hw
* addr bit addr bit in out irq name pin offset
*
* 0x7b 0 0x7a 0 x x DIO1_0 1 0
* 0x7b 1 0x7a 0 x x DIO1_1 3 1
* 0x7b 2 0x7a 0 x x DIO1_2 5 2
* 0x7b 3 0x7a 0 x x DIO1_3 7 3
* 0x7b 4 0x7a 1 x x DIO1_4 9 4
* 0x7b 5 0x7a 1 x x DIO1_5 11 5
* 0x7b 6 0x7a 1 x x DIO1_6 13 6
* 0x7b 7 0x7a 1 x x DIO1_7 15 7
* 0x7c 0 0x7a 5 x x DIO1_8 4 8
* 0x7c 1 0x7a 5 x x DIO1_9 6 9
* 0x7c 2 0x7a 5 x x DIO1_10 8 10
* 0x7c 3 0x7a 5 x x DIO1_11 10 11
* 0x7c 4 x DIO1_12 12 12
* 0x7c 5 x 7 DIO1_13 14 13
*/
static const struct ts5500_dio ts5500_dio1[] = {
TS5500_DIO_GROUP(0x7b, 0, 0x7a, 0),
TS5500_DIO_GROUP(0x7b, 4, 0x7a, 1),
TS5500_DIO_GROUP(0x7c, 0, 0x7a, 5),
TS5500_DIO_IN(0x7c, 4),
TS5500_DIO_IN_IRQ(0x7c, 5, 7),
};
/*
* TS-5500 DIO2 block
*
* value control dir hw
* addr bit addr bit in out irq name pin offset
*
* 0x7e 0 0x7d 0 x x DIO2_0 1 0
* 0x7e 1 0x7d 0 x x DIO2_1 3 1
* 0x7e 2 0x7d 0 x x DIO2_2 5 2
* 0x7e 3 0x7d 0 x x DIO2_3 7 3
* 0x7e 4 0x7d 1 x x DIO2_4 9 4
* 0x7e 5 0x7d 1 x x DIO2_5 11 5
* 0x7e 6 0x7d 1 x x DIO2_6 13 6
* 0x7e 7 0x7d 1 x x DIO2_7 15 7
* 0x7f 0 0x7d 5 x x DIO2_8 4 8
* 0x7f 1 0x7d 5 x x DIO2_9 6 9
* 0x7f 2 0x7d 5 x x DIO2_10 8 10
* 0x7f 3 0x7d 5 x x DIO2_11 10 11
* 0x7f 4 x 6 DIO2_13 14 12
*/
static const struct ts5500_dio ts5500_dio2[] = {
TS5500_DIO_GROUP(0x7e, 0, 0x7d, 0),
TS5500_DIO_GROUP(0x7e, 4, 0x7d, 1),
TS5500_DIO_GROUP(0x7f, 0, 0x7d, 5),
TS5500_DIO_IN_IRQ(0x7f, 4, 6),
};
/*
* TS-5500 LCD port used as DIO block
* TS-5600 LCD port is identical
*
* value control dir hw
* addr bit addr bit in out irq name pin offset
*
* 0x72 0 0x7d 2 x x LCD_0 8 0
* 0x72 1 0x7d 2 x x LCD_1 7 1
* 0x72 2 0x7d 2 x x LCD_2 10 2
* 0x72 3 0x7d 2 x x LCD_3 9 3
* 0x72 4 0x7d 3 x x LCD_4 12 4
* 0x72 5 0x7d 3 x x LCD_5 11 5
* 0x72 6 0x7d 3 x x LCD_6 14 6
* 0x72 7 0x7d 3 x x LCD_7 13 7
* 0x73 0 x LCD_EN 5 8
* 0x73 6 x LCD_WR 6 9
* 0x73 7 x 1 LCD_RS 3 10
*/
static const struct ts5500_dio ts5500_lcd[] = {
TS5500_DIO_GROUP(0x72, 0, 0x7d, 2),
TS5500_DIO_GROUP(0x72, 4, 0x7d, 3),
TS5500_DIO_OUT(0x73, 0),
TS5500_DIO_IN(0x73, 6),
TS5500_DIO_IN_IRQ(0x73, 7, 1),
};
static inline void ts5500_set_mask(u8 mask, u8 addr)
{
u8 val = inb(addr);
val |= mask;
outb(val, addr);
}
static inline void ts5500_clear_mask(u8 mask, u8 addr)
{
u8 val = inb(addr);
val &= ~mask;
outb(val, addr);
}
static int ts5500_gpio_input(struct gpio_chip *chip, unsigned offset)
{
struct ts5500_priv *priv = gpiochip_get_data(chip);
const struct ts5500_dio line = priv->pinout[offset];
unsigned long flags;
if (line.no_input)
return -ENXIO;
if (line.no_output)
return 0;
spin_lock_irqsave(&priv->lock, flags);
ts5500_clear_mask(line.control_mask, line.control_addr);
spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static int ts5500_gpio_get(struct gpio_chip *chip, unsigned offset)
{
struct ts5500_priv *priv = gpiochip_get_data(chip);
const struct ts5500_dio line = priv->pinout[offset];
return !!(inb(line.value_addr) & line.value_mask);
}
static int ts5500_gpio_output(struct gpio_chip *chip, unsigned offset, int val)
{
struct ts5500_priv *priv = gpiochip_get_data(chip);
const struct ts5500_dio line = priv->pinout[offset];
unsigned long flags;
if (line.no_output)
return -ENXIO;
spin_lock_irqsave(&priv->lock, flags);
if (!line.no_input)
ts5500_set_mask(line.control_mask, line.control_addr);
if (val)
ts5500_set_mask(line.value_mask, line.value_addr);
else
ts5500_clear_mask(line.value_mask, line.value_addr);
spin_unlock_irqrestore(&priv->lock, flags);
return 0;
}
static void ts5500_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
struct ts5500_priv *priv = gpiochip_get_data(chip);
const struct ts5500_dio line = priv->pinout[offset];
unsigned long flags;
spin_lock_irqsave(&priv->lock, flags);
if (val)
ts5500_set_mask(line.value_mask, line.value_addr);
else
ts5500_clear_mask(line.value_mask, line.value_addr);
spin_unlock_irqrestore(&priv->lock, flags);
}
static int ts5500_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
{
struct ts5500_priv *priv = gpiochip_get_data(chip);
const struct ts5500_dio *block = priv->pinout;
const struct ts5500_dio line = block[offset];
/* Only one pin is connected to an interrupt */
if (line.irq)
return line.irq;
/* As this pin is input-only, we may strap it to another in/out pin */
if (priv->strap)
return priv->hwirq;
return -ENXIO;
}
static int ts5500_enable_irq(struct ts5500_priv *priv)
{
int ret = 0;
unsigned long flags;
spin_lock_irqsave(&priv->lock, flags);
if (priv->hwirq == 7)
ts5500_set_mask(BIT(7), 0x7a); /* DIO1_13 on IRQ7 */
else if (priv->hwirq == 6)
ts5500_set_mask(BIT(7), 0x7d); /* DIO2_13 on IRQ6 */
else if (priv->hwirq == 1)
ts5500_set_mask(BIT(6), 0x7d); /* LCD_RS on IRQ1 */
else
ret = -EINVAL;
spin_unlock_irqrestore(&priv->lock, flags);
return ret;
}
static void ts5500_disable_irq(struct ts5500_priv *priv)
{
unsigned long flags;
spin_lock_irqsave(&priv->lock, flags);
if (priv->hwirq == 7)
ts5500_clear_mask(BIT(7), 0x7a); /* DIO1_13 on IRQ7 */
else if (priv->hwirq == 6)
ts5500_clear_mask(BIT(7), 0x7d); /* DIO2_13 on IRQ6 */
else if (priv->hwirq == 1)
ts5500_clear_mask(BIT(6), 0x7d); /* LCD_RS on IRQ1 */
else
dev_err(priv->gpio_chip.parent, "invalid hwirq %d\n",
priv->hwirq);
spin_unlock_irqrestore(&priv->lock, flags);
}
static int ts5500_dio_probe(struct platform_device *pdev)
{
enum ts5500_blocks block = platform_get_device_id(pdev)->driver_data;
struct device *dev = &pdev->dev;
const char *name = dev_name(dev);
struct ts5500_priv *priv;
struct resource *res;
unsigned long flags;
int ret;
res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!res) {
dev_err(dev, "missing IRQ resource\n");
return -EINVAL;
}
priv = devm_kzalloc(dev, sizeof(struct ts5500_priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
platform_set_drvdata(pdev, priv);
priv->hwirq = res->start;
spin_lock_init(&priv->lock);
priv->gpio_chip.owner = THIS_MODULE;
priv->gpio_chip.label = name;
priv->gpio_chip.parent = dev;
priv->gpio_chip.direction_input = ts5500_gpio_input;
priv->gpio_chip.direction_output = ts5500_gpio_output;
priv->gpio_chip.get = ts5500_gpio_get;
priv->gpio_chip.set = ts5500_gpio_set;
priv->gpio_chip.to_irq = ts5500_gpio_to_irq;
priv->gpio_chip.base = -1;
switch (block) {
case TS5500_DIO1:
priv->pinout = ts5500_dio1;
priv->gpio_chip.ngpio = ARRAY_SIZE(ts5500_dio1);
if (!devm_request_region(dev, 0x7a, 3, name)) {
dev_err(dev, "failed to request %s ports\n", name);
return -EBUSY;
}
break;
case TS5500_DIO2:
priv->pinout = ts5500_dio2;
priv->gpio_chip.ngpio = ARRAY_SIZE(ts5500_dio2);
if (!devm_request_region(dev, 0x7e, 2, name)) {
dev_err(dev, "failed to request %s ports\n", name);
return -EBUSY;
}
if (hex7d_reserved)
break;
if (!devm_request_region(dev, 0x7d, 1, name)) {
dev_err(dev, "failed to request %s 7D\n", name);
return -EBUSY;
}
hex7d_reserved = true;
break;
case TS5500_LCD:
case TS5600_LCD:
priv->pinout = ts5500_lcd;
priv->gpio_chip.ngpio = ARRAY_SIZE(ts5500_lcd);
if (!devm_request_region(dev, 0x72, 2, name)) {
dev_err(dev, "failed to request %s ports\n", name);
return -EBUSY;
}
if (!hex7d_reserved) {
if (!devm_request_region(dev, 0x7d, 1, name)) {
dev_err(dev, "failed to request %s 7D\n", name);
return -EBUSY;
}
hex7d_reserved = true;
}
/* Ensure usage of LCD port as DIO */
spin_lock_irqsave(&priv->lock, flags);
ts5500_clear_mask(BIT(4), 0x7d);
spin_unlock_irqrestore(&priv->lock, flags);
break;
}
ret = devm_gpiochip_add_data(dev, &priv->gpio_chip, priv);
if (ret) {
dev_err(dev, "failed to register the gpio chip\n");
return ret;
}
ret = ts5500_enable_irq(priv);
if (ret) {
dev_err(dev, "invalid interrupt %d\n", priv->hwirq);
return ret;
}
return 0;
}
static int ts5500_dio_remove(struct platform_device *pdev)
{
struct ts5500_priv *priv = platform_get_drvdata(pdev);
ts5500_disable_irq(priv);
return 0;
}
static const struct platform_device_id ts5500_dio_ids[] = {
{ "ts5500-dio1", TS5500_DIO1 },
{ "ts5500-dio2", TS5500_DIO2 },
{ "ts5500-dio-lcd", TS5500_LCD },
{ "ts5600-dio-lcd", TS5600_LCD },
{ }
};
MODULE_DEVICE_TABLE(platform, ts5500_dio_ids);
static struct platform_driver ts5500_dio_driver = {
.driver = {
.name = "ts5500-dio",
},
.probe = ts5500_dio_probe,
.remove = ts5500_dio_remove,
.id_table = ts5500_dio_ids,
};
module_platform_driver(ts5500_dio_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Savoir-faire Linux Inc. <kernel@savoirfairelinux.com>");
MODULE_DESCRIPTION("Technologic Systems TS-5500 Digital I/O driver");
