linux/drivers/gpio/gpio-etraxfs.c
Rabin Vincent d342571efe gpio: add ETRAXFS GPIO driver
Add a GPIO driver for the General I/O block on Axis ETRAX FS SoCs.

Signed-off-by: Rabin Vincent <rabin@rab.in>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2015-06-10 09:11:10 +02:00

177 lines
3.9 KiB
C

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/gpio.h>
#include <linux/of_gpio.h>
#include <linux/io.h>
#include <linux/platform_device.h>
#include <linux/basic_mmio_gpio.h>
#define ETRAX_FS_rw_pa_dout 0
#define ETRAX_FS_r_pa_din 4
#define ETRAX_FS_rw_pa_oe 8
#define ETRAX_FS_rw_intr_cfg 12
#define ETRAX_FS_rw_intr_mask 16
#define ETRAX_FS_rw_ack_intr 20
#define ETRAX_FS_r_intr 24
#define ETRAX_FS_rw_pb_dout 32
#define ETRAX_FS_r_pb_din 36
#define ETRAX_FS_rw_pb_oe 40
#define ETRAX_FS_rw_pc_dout 48
#define ETRAX_FS_r_pc_din 52
#define ETRAX_FS_rw_pc_oe 56
#define ETRAX_FS_rw_pd_dout 64
#define ETRAX_FS_r_pd_din 68
#define ETRAX_FS_rw_pd_oe 72
#define ETRAX_FS_rw_pe_dout 80
#define ETRAX_FS_r_pe_din 84
#define ETRAX_FS_rw_pe_oe 88
struct etraxfs_gpio_port {
const char *label;
unsigned int oe;
unsigned int dout;
unsigned int din;
unsigned int ngpio;
};
struct etraxfs_gpio_info {
unsigned int num_ports;
const struct etraxfs_gpio_port *ports;
};
static const struct etraxfs_gpio_port etraxfs_gpio_etraxfs_ports[] = {
{
.label = "A",
.ngpio = 8,
.oe = ETRAX_FS_rw_pa_oe,
.dout = ETRAX_FS_rw_pa_dout,
.din = ETRAX_FS_r_pa_din,
},
{
.label = "B",
.ngpio = 18,
.oe = ETRAX_FS_rw_pb_oe,
.dout = ETRAX_FS_rw_pb_dout,
.din = ETRAX_FS_r_pb_din,
},
{
.label = "C",
.ngpio = 18,
.oe = ETRAX_FS_rw_pc_oe,
.dout = ETRAX_FS_rw_pc_dout,
.din = ETRAX_FS_r_pc_din,
},
{
.label = "D",
.ngpio = 18,
.oe = ETRAX_FS_rw_pd_oe,
.dout = ETRAX_FS_rw_pd_dout,
.din = ETRAX_FS_r_pd_din,
},
{
.label = "E",
.ngpio = 18,
.oe = ETRAX_FS_rw_pe_oe,
.dout = ETRAX_FS_rw_pe_dout,
.din = ETRAX_FS_r_pe_din,
},
};
static const struct etraxfs_gpio_info etraxfs_gpio_etraxfs = {
.num_ports = ARRAY_SIZE(etraxfs_gpio_etraxfs_ports),
.ports = etraxfs_gpio_etraxfs_ports,
};
static int etraxfs_gpio_of_xlate(struct gpio_chip *gc,
const struct of_phandle_args *gpiospec,
u32 *flags)
{
/*
* Port numbers are A to E, and the properties are integers, so we
* specify them as 0xA - 0xE.
*/
if (gc->label[0] - 'A' + 0xA != gpiospec->args[2])
return -EINVAL;
return of_gpio_simple_xlate(gc, gpiospec, flags);
}
static const struct of_device_id etraxfs_gpio_of_table[] = {
{
.compatible = "axis,etraxfs-gio",
.data = &etraxfs_gpio_etraxfs,
},
{},
};
static int etraxfs_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
const struct etraxfs_gpio_info *info;
const struct of_device_id *match;
struct bgpio_chip *chips;
struct resource *res;
void __iomem *regs;
int ret;
int i;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
regs = devm_ioremap_resource(dev, res);
if (!regs)
return -ENOMEM;
match = of_match_node(etraxfs_gpio_of_table, dev->of_node);
if (!match)
return -EINVAL;
info = match->data;
chips = devm_kzalloc(dev, sizeof(*chips) * info->num_ports, GFP_KERNEL);
if (!chips)
return -ENOMEM;
for (i = 0; i < info->num_ports; i++) {
struct bgpio_chip *bgc = &chips[i];
const struct etraxfs_gpio_port *port = &info->ports[i];
ret = bgpio_init(bgc, dev, 4,
regs + port->din, /* dat */
regs + port->dout, /* set */
NULL, /* clr */
regs + port->oe, /* dirout */
NULL, /* dirin */
BGPIOF_UNREADABLE_REG_SET);
if (ret)
return ret;
bgc->gc.ngpio = port->ngpio;
bgc->gc.label = port->label;
bgc->gc.of_node = dev->of_node;
bgc->gc.of_gpio_n_cells = 3;
bgc->gc.of_xlate = etraxfs_gpio_of_xlate;
ret = gpiochip_add(&bgc->gc);
if (ret)
dev_err(dev, "Unable to register port %s\n",
bgc->gc.label);
}
return 0;
}
static struct platform_driver etraxfs_gpio_driver = {
.driver = {
.name = "etraxfs-gpio",
.of_match_table = of_match_ptr(etraxfs_gpio_of_table),
},
.probe = etraxfs_gpio_probe,
};
static int __init etraxfs_gpio_init(void)
{
return platform_driver_register(&etraxfs_gpio_driver);
}
device_initcall(etraxfs_gpio_init);