Re: [PATCH 02/47] Add new driver files for Artpec-3.

[David Brownell]

This is needlessly arch-specific though... some other recent platform updates
have provided the Documentation/gpio.txt interfaces and plan to update them
to use the new gpiolib infrastructure when that hits mainline.  That gives a
simpler and more extensible approach to I2C (or SPI, etc) GPIO expanders.

I'd guess this talks to a pcf8575-ish GPIO expander (16 bits) though the
code rather lacks relevant comments...

The GPIO feature here that's not yet in mainline is a userspace interface.
I think that gpiolib will make it a lot easier to offer one of those, since
it maintains a registry that didn't previously exist.

I'm a bit surprised that this doesn't seem to offer kernel interfaces for
GPIOs.  There seems to be no way for drivers to use them for input/output
(other than direct register access, which won't work with e.g. leds-gpio
or i2c-gpio) or request_irq(...) for something coming from a GPIO.

The LED stuff, and PWM support, should IMO be managed separately.  We have
a LED framework that's preferable to this stuff.  PWM is a different issue;
I have a hard time imagining a good generic PWM framework, but maybe that's
because I don't use PWM for anything interesting (like motor control), just
for simple LED/backlight brightness control.

- Dave


> --- /dev/null
> +++ b/arch/cris/arch-v32/drivers/mach-a3/gpio.c
> @@ -0,0 +1,984 @@
> +/*
> + * Artec-3 general port I/O device
> + *
> + * Copyright (c) 2007 Axis Communications AB
> + *
> + * Authors:    Bjorn Wesen      (initial version)
> + *             Ola Knutsson     (LED handling)
> + *             Johan Adolfsson  (read/set directions, write, port G,
> + *                               port to ETRAX FS.
> + *             Ricard Wanderlof (PWM for Artpec-3)
> + *
> + */
> +
> +#include <linux/module.h>
> +#include <linux/sched.h>
> +#include <linux/slab.h>
> +#include <linux/ioport.h>
> +#include <linux/errno.h>
> +#include <linux/kernel.h>
> +#include <linux/fs.h>
> +#include <linux/string.h>
> +#include <linux/poll.h>
> +#include <linux/init.h>
> +#include <linux/interrupt.h>
> +#include <linux/spinlock.h>
> +
> +#include <asm/etraxgpio.h>
> +#include <hwregs/reg_map.h>
> +#include <hwregs/reg_rdwr.h>
> +#include <hwregs/gio_defs.h>
> +#include <hwregs/intr_vect_defs.h>
> +#include <asm/io.h>
> +#include <asm/system.h>
> +#include <asm/irq.h>
> +#include <asm/arch/mach/pinmux.h>
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +#include "../i2c.h"
> +
> +#define VIRT_I2C_ADDR 0x40
> +#endif
> +
> +/* The following gio ports on ARTPEC-3 is available:
> + * pa 32 bits
> + * pb 32 bits
> + * pc 16 bits
> + * each port has a rw_px_dout, r_px_din and rw_px_oe register.
> + */
> +
> +#define GPIO_MAJOR 120  /* experimental MAJOR number */
> +
> +#define I2C_INTERRUPT_BITS 0x300 /* i2c0_done and i2c1_done bits */
> +
> +#define D(x)
> +
> +#if 0
> +static int dp_cnt;
> +#define DP(x) \
> +	do { \
> +		dp_cnt++; \
> +		if (dp_cnt % 1000 == 0) \
> +			x; \
> +	} while (0)
> +#else
> +#define DP(x)
> +#endif
> +
> +static char gpio_name[] = "etrax gpio";
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +static int virtual_gpio_ioctl(struct file *file, unsigned int cmd,
> +			      unsigned long arg);
> +#endif
> +static int gpio_ioctl(struct inode *inode, struct file *file,
> +		      unsigned int cmd, unsigned long arg);
> +static ssize_t gpio_write(struct file *file, const char *buf, size_t count,
> +			  loff_t *off);
> +static int gpio_open(struct inode *inode, struct file *filp);
> +static int gpio_release(struct inode *inode, struct file *filp);
> +static unsigned int gpio_poll(struct file *filp,
> +			      struct poll_table_struct *wait);
> +
> +/* private data per open() of this driver */
> +
> +struct gpio_private {
> +	struct gpio_private *next;
> +	/* The IO_CFG_WRITE_MODE_VALUE only support 8 bits: */
> +	unsigned char clk_mask;
> +	unsigned char data_mask;
> +	unsigned char write_msb;
> +	unsigned char pad1;
> +	/* These fields are generic */
> +	unsigned long highalarm, lowalarm;
> +	wait_queue_head_t alarm_wq;
> +	int minor;
> +};
> +
> +static void gpio_set_alarm(struct gpio_private *priv);
> +
> +/* linked list of alarms to check for */
> +
> +static struct gpio_private *alarmlist;
> +
> +static int wanted_interrupts;
> +
> +static DEFINE_SPINLOCK(alarm_lock);
> +
> +#define NUM_PORTS (GPIO_MINOR_LAST+1)
> +#define GIO_REG_RD_ADDR(reg) \
> +	(volatile unsigned long *)(regi_gio + REG_RD_ADDR_gio_##reg)
> +#define GIO_REG_WR_ADDR(reg) \
> +	(volatile unsigned long *)(regi_gio + REG_WR_ADDR_gio_##reg)
> +unsigned long led_dummy;
> +unsigned long port_d_dummy;	/* Only input on Artpec-3 */
> +unsigned long port_e_dummy;	/* Non existent on Artpec-3 */
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +static unsigned long virtual_dummy;
> +static unsigned long virtual_rw_pv_oe = CONFIG_ETRAX_DEF_GIO_PV_OE;
> +static unsigned short cached_virtual_gpio_read;
> +#endif
> +
> +static volatile unsigned long *data_out[NUM_PORTS] = {
> +	GIO_REG_WR_ADDR(rw_pa_dout),
> +	GIO_REG_WR_ADDR(rw_pb_dout),
> +	&led_dummy,
> +	GIO_REG_WR_ADDR(rw_pc_dout),
> +	&port_d_dummy,
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	&port_e_dummy,
> +	&virtual_dummy,
> +#endif
> +};
> +
> +static volatile unsigned long *data_in[NUM_PORTS] = {
> +	GIO_REG_RD_ADDR(r_pa_din),
> +	GIO_REG_RD_ADDR(r_pb_din),
> +	&led_dummy,
> +	GIO_REG_RD_ADDR(r_pc_din),
> +	GIO_REG_RD_ADDR(r_pd_din),
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	&port_e_dummy,
> +	&virtual_dummy,
> +#endif
> +};
> +
> +static unsigned long changeable_dir[NUM_PORTS] = {
> +	CONFIG_ETRAX_PA_CHANGEABLE_DIR,
> +	CONFIG_ETRAX_PB_CHANGEABLE_DIR,
> +	0,
> +	CONFIG_ETRAX_PC_CHANGEABLE_DIR,
> +	0,
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	0,
> +	CONFIG_ETRAX_PV_CHANGEABLE_DIR,
> +#endif
> +};
> +
> +static unsigned long changeable_bits[NUM_PORTS] = {
> +	CONFIG_ETRAX_PA_CHANGEABLE_BITS,
> +	CONFIG_ETRAX_PB_CHANGEABLE_BITS,
> +	0,
> +	CONFIG_ETRAX_PC_CHANGEABLE_BITS,
> +	0,
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	0,
> +	CONFIG_ETRAX_PV_CHANGEABLE_BITS,
> +#endif
> +};
> +
> +static volatile unsigned long *dir_oe[NUM_PORTS] = {
> +	GIO_REG_WR_ADDR(rw_pa_oe),
> +	GIO_REG_WR_ADDR(rw_pb_oe),
> +	&led_dummy,
> +	GIO_REG_WR_ADDR(rw_pc_oe),
> +	&port_d_dummy,
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	&port_e_dummy,
> +	&virtual_rw_pv_oe,
> +#endif
> +};
> +
> +static void
> +gpio_set_alarm(struct gpio_private *priv)
> +{
> +	int bit;
> +	int intr_cfg;
> +	int mask;
> +	int pins;
> +	unsigned long flags;
> +
> +	local_irq_save(flags);
> +	intr_cfg = REG_RD_INT(gio, regi_gio, rw_intr_cfg);
> +	pins = REG_RD_INT(gio, regi_gio, rw_intr_pins);
> +	mask = REG_RD_INT(gio, regi_gio, rw_intr_mask) & I2C_INTERRUPT_BITS;
> +
> +	for (bit = 0; bit < 32; bit++) {
> +		int intr = bit % 8;
> +		int pin = bit / 8;
> +		if (priv->minor < GPIO_MINOR_LEDS)
> +			pin += priv->minor * 4;
> +		else
> +			pin += (priv->minor - 1) * 4;
> +
> +		if (priv->highalarm & (1<<bit)) {
> +			intr_cfg |= (regk_gio_hi << (intr * 3));
> +			mask |= 1 << intr;
> +			wanted_interrupts = mask & 0xff;
> +			pins |= pin << (intr * 4);
> +		} else if (priv->lowalarm & (1<<bit)) {
> +			intr_cfg |= (regk_gio_lo << (intr * 3));
> +			mask |= 1 << intr;
> +			wanted_interrupts = mask & 0xff;
> +			pins |= pin << (intr * 4);
> +		}
> +	}
> +
> +	REG_WR_INT(gio, regi_gio, rw_intr_cfg, intr_cfg);
> +	REG_WR_INT(gio, regi_gio, rw_intr_pins, pins);
> +	REG_WR_INT(gio, regi_gio, rw_intr_mask, mask);
> +
> +	local_irq_restore(flags);
> +}
> +
> +static unsigned int
> +gpio_poll(struct file *file, struct poll_table_struct *wait)
> +{
> +	unsigned int mask = 0;
> +	struct gpio_private *priv = (struct gpio_private *)file->private_data;
> +	unsigned long data;
> +	unsigned long tmp;
> +
> +	if (priv->minor >= GPIO_MINOR_PWM0 &&
> +	    priv->minor <= GPIO_MINOR_LAST_PWM)
> +		return 0;
> +
> +	poll_wait(file, &priv->alarm_wq, wait);
> +	if (priv->minor <= GPIO_MINOR_D) {
> +		data = *data_in[priv->minor];
> +		REG_WR_INT(gio, regi_gio, rw_ack_intr, wanted_interrupts);
> +		tmp = REG_RD_INT(gio, regi_gio, rw_intr_mask);
> +		tmp &= I2C_INTERRUPT_BITS;
> +		tmp |= wanted_interrupts;
> +		REG_WR_INT(gio, regi_gio, rw_intr_mask, tmp);
> +	} else
> +		return 0;
> +
> +	if ((data & priv->highalarm) || (~data & priv->lowalarm))
> +		mask = POLLIN|POLLRDNORM;
> +
> +	DP(printk(KERN_DEBUG "gpio_poll ready: mask 0x%08X\n", mask));
> +	return mask;
> +}
> +
> +static irqreturn_t
> +gpio_interrupt(int irq, void *dev_id)
> +{
> +	reg_gio_rw_intr_mask intr_mask;
> +	reg_gio_r_masked_intr masked_intr;
> +	reg_gio_rw_ack_intr ack_intr;
> +	unsigned long tmp;
> +	unsigned long tmp2;
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	unsigned char enable_gpiov_ack = 0;
> +#endif
> +
> +	/* Find what PA interrupts are active */
> +	masked_intr = REG_RD(gio, regi_gio, r_masked_intr);
> +	tmp = REG_TYPE_CONV(unsigned long, reg_gio_r_masked_intr, masked_intr);
> +
> +	/* Find those that we have enabled */
> +	spin_lock(&alarm_lock);
> +	tmp &= wanted_interrupts;
> +	spin_unlock(&alarm_lock);
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	/* Something changed on virtual GPIO. Interrupt is acked by
> +	 * reading the device.
> +	 */
> +	if (tmp & (1 << CONFIG_ETRAX_VIRTUAL_GPIO_INTERRUPT_PA_PIN)) {
> +		i2c_read(VIRT_I2C_ADDR, (void *)&cached_virtual_gpio_read,
> +			sizeof(cached_virtual_gpio_read));
> +		enable_gpiov_ack = 1;
> +	}
> +#endif
> +
> +	/* Ack them */
> +	ack_intr = REG_TYPE_CONV(reg_gio_rw_ack_intr, unsigned long, tmp);
> +	REG_WR(gio, regi_gio, rw_ack_intr, ack_intr);
> +
> +	/* Disable those interrupts.. */
> +	intr_mask = REG_RD(gio, regi_gio, rw_intr_mask);
> +	tmp2 = REG_TYPE_CONV(unsigned long, reg_gio_rw_intr_mask, intr_mask);
> +	tmp2 &= ~tmp;
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	/* Do not disable interrupt on virtual GPIO. Changes on virtual
> +	 * pins are only noticed by an interrupt.
> +	 */
> +	if (enable_gpiov_ack)
> +		tmp2 |= (1 << CONFIG_ETRAX_VIRTUAL_GPIO_INTERRUPT_PA_PIN);
> +#endif
> +	intr_mask = REG_TYPE_CONV(reg_gio_rw_intr_mask, unsigned long, tmp2);
> +	REG_WR(gio, regi_gio, rw_intr_mask, intr_mask);
> +
> +	return IRQ_RETVAL(tmp);
> +}
> +
> +
> +static ssize_t gpio_write(struct file *file, const char *buf, size_t count,
> +	loff_t *off)
> +{
> +	struct gpio_private *priv = (struct gpio_private *)file->private_data;
> +	unsigned char data, clk_mask, data_mask, write_msb;
> +	unsigned long flags;
> +	unsigned long shadow;
> +	volatile unsigned long *port;
> +	ssize_t retval = count;
> +	/* Only bits 0-7 may be used for write operations but allow all
> +	   devices except leds... */
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	if (priv->minor == GPIO_MINOR_V)
> +		return -EFAULT;
> +#endif
> +	if (priv->minor == GPIO_MINOR_LEDS)
> +		return -EFAULT;
> +
> +	if (priv->minor >= GPIO_MINOR_PWM0 &&
> +	    priv->minor <= GPIO_MINOR_LAST_PWM)
> +		return -EFAULT;
> +
> +	if (!access_ok(VERIFY_READ, buf, count))
> +		return -EFAULT;
> +
> +	clk_mask = priv->clk_mask;
> +	data_mask = priv->data_mask;
> +	/* It must have been configured using the IO_CFG_WRITE_MODE */
> +	/* Perhaps a better error code? */
> +	if (clk_mask == 0 || data_mask == 0)
> +		return -EPERM;
> +
> +	write_msb = priv->write_msb;
> +	D(printk(KERN_DEBUG "gpio_write: %lu to data 0x%02X clk 0x%02X "
> +		"msb: %i\n",
> +		count, data_mask, clk_mask, write_msb));
> +	port = data_out[priv->minor];
> +
> +	while (count--) {
> +		int i;
> +		data = *buf++;
> +		if (priv->write_msb) {
> +			for (i = 7; i >= 0; i--) {
> +				local_irq_save(flags);
> +				shadow = *port;
> +				*port = shadow &= ~clk_mask;
> +				if (data & 1<<i)
> +					*port = shadow |= data_mask;
> +				else
> +					*port = shadow &= ~data_mask;
> +			/* For FPGA: min 5.0ns (DCC) before CCLK high */
> +				*port = shadow |= clk_mask;
> +				local_irq_restore(flags);
> +			}
> +		} else {
> +			for (i = 0; i <= 7; i++) {
> +				local_irq_save(flags);
> +				shadow = *port;
> +				*port = shadow &= ~clk_mask;
> +				if (data & 1<<i)
> +					*port = shadow |= data_mask;
> +				else
> +					*port = shadow &= ~data_mask;
> +			/* For FPGA: min 5.0ns (DCC) before CCLK high */
> +				*port = shadow |= clk_mask;
> +				local_irq_restore(flags);
> +			}
> +		}
> +	}
> +	return retval;
> +}
> +
> +static int
> +gpio_open(struct inode *inode, struct file *filp)
> +{
> +	struct gpio_private *priv;
> +	int p = iminor(inode);
> +
> +	if (p > GPIO_MINOR_LAST_PWM ||
> +	    (p > GPIO_MINOR_LAST && p < GPIO_MINOR_PWM0))
> +		return -EINVAL;
> +
> +	priv = kmalloc(sizeof(struct gpio_private), GFP_KERNEL);
> +
> +	if (!priv)
> +		return -ENOMEM;
> +	memset(priv, 0, sizeof(*priv));
> +
> +	priv->minor = p;
> +	filp->private_data = (void *)priv;
> +
> +	/* initialize the io/alarm struct, not for PWM ports though  */
> +	if (p <= GPIO_MINOR_LAST) {
> +
> +		priv->clk_mask = 0;
> +		priv->data_mask = 0;
> +		priv->highalarm = 0;
> +		priv->lowalarm = 0;
> +
> +		init_waitqueue_head(&priv->alarm_wq);
> +
> +		/* link it into our alarmlist */
> +		spin_lock_irq(&alarm_lock);
> +		priv->next = alarmlist;
> +		alarmlist = priv;
> +		spin_unlock_irq(&alarm_lock);
> +	}
> +
> +	return 0;
> +}
> +
> +static int
> +gpio_release(struct inode *inode, struct file *filp)
> +{
> +	struct gpio_private *p;
> +	struct gpio_private *todel;
> +	/* local copies while updating them: */
> +	unsigned long a_high, a_low;
> +
> +	/* prepare to free private structure */
> +	todel = (struct gpio_private *)filp->private_data;
> +
> +	/* unlink from alarmlist - only for non-PWM ports though */
> +	if (todel->minor <= GPIO_MINOR_LAST) {
> +		spin_lock_irq(&alarm_lock);
> +		p = alarmlist;
> +
> +		if (p == todel)
> +			alarmlist = todel->next;
> +		 else {
> +			while (p->next != todel)
> +				p = p->next;
> +			p->next = todel->next;
> +		}
> +
> +		/* Check if there are still any alarms set */
> +		p = alarmlist;
> +		a_high = 0;
> +		a_low = 0;
> +		while (p) {
> +			if (p->minor == GPIO_MINOR_A) {
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +				p->lowalarm |= (1 << CONFIG_ETRAX_VIRTUAL_GPIO_INTERRUPT_PA_PIN);
> +#endif
> +				a_high |= p->highalarm;
> +				a_low |= p->lowalarm;
> +			}
> +
> +			p = p->next;
> +		}
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	/* Variable 'a_low' needs to be set here again
> +	 * to ensure that interrupt for virtual GPIO is handled.
> +	 */
> +		a_low |= (1 << CONFIG_ETRAX_VIRTUAL_GPIO_INTERRUPT_PA_PIN);
> +#endif
> +
> +		spin_unlock_irq(&alarm_lock);
> +	}
> +	kfree(todel);
> +
> +	return 0;
> +}
> +
> +/* Main device API. ioctl's to read/set/clear bits, as well as to
> + * set alarms to wait for using a subsequent select().
> + */
> +
> +inline unsigned long setget_input(struct gpio_private *priv, unsigned long arg)
> +{
> +	/* Set direction 0=unchanged 1=input,
> +	 * return mask with 1=input
> +	 */
> +	unsigned long flags;
> +	unsigned long dir_shadow;
> +
> +	local_irq_save(flags);
> +	dir_shadow = *dir_oe[priv->minor];
> +	dir_shadow &= ~(arg & changeable_dir[priv->minor]);
> +	*dir_oe[priv->minor] = dir_shadow;
> +	local_irq_restore(flags);
> +
> +	if (priv->minor == GPIO_MINOR_C)
> +		dir_shadow ^= 0xFFFF;		/* Only 16 bits */
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	else if (priv->minor == GPIO_MINOR_V)
> +		dir_shadow ^= 0xFFFF;		/* Only 16 bits */
> +#endif
> +	else
> +		dir_shadow ^= 0xFFFFFFFF;	/* PA, PB and PD 32 bits */
> +
> +	return dir_shadow;
> +
> +} /* setget_input */
> +
> +inline unsigned long setget_output(struct gpio_private *priv, unsigned long arg)
> +{
> +	unsigned long flags;
> +	unsigned long dir_shadow;
> +
> +	local_irq_save(flags);
> +	dir_shadow = *dir_oe[priv->minor];
> +	dir_shadow |=  (arg & changeable_dir[priv->minor]);
> +	*dir_oe[priv->minor] = dir_shadow;
> +	local_irq_restore(flags);
> +	return dir_shadow;
> +} /* setget_output */
> +
> +static int
> +gpio_leds_ioctl(unsigned int cmd, unsigned long arg);
> +
> +static int
> +gpio_pwm_ioctl(struct gpio_private *priv, unsigned int cmd, unsigned long arg);
> +
> +static int
> +gpio_ioctl(struct inode *inode, struct file *file,
> +	   unsigned int cmd, unsigned long arg)
> +{
> +	unsigned long flags;
> +	unsigned long val;
> +	unsigned long shadow;
> +	struct gpio_private *priv = (struct gpio_private *)file->private_data;
> +
> +	if (_IOC_TYPE(cmd) != ETRAXGPIO_IOCTYPE)
> +		return -EINVAL;
> +
> +	/* Check for special ioctl handlers first */
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	if (priv->minor == GPIO_MINOR_V)
> +		return virtual_gpio_ioctl(file, cmd, arg);
> +#endif
> +
> +	if (priv->minor == GPIO_MINOR_LEDS)
> +		return gpio_leds_ioctl(cmd, arg);
> +
> +	if (priv->minor >= GPIO_MINOR_PWM0 &&
> +	    priv->minor <= GPIO_MINOR_LAST_PWM)
> +		return gpio_pwm_ioctl(priv, cmd, arg);
> +
> +	switch (_IOC_NR(cmd)) {
> +	case IO_READBITS: /* Use IO_READ_INBITS and IO_READ_OUTBITS instead */
> +		/* Read the port. */
> +		return *data_in[priv->minor];
> +		break;
> +	case IO_SETBITS:
> +		local_irq_save(flags);
> +		/* Set changeable bits with a 1 in arg. */
> +		shadow = *data_out[priv->minor];
> +		shadow |=  (arg & changeable_bits[priv->minor]);
> +		*data_out[priv->minor] = shadow;
> +		local_irq_restore(flags);
> +		break;
> +	case IO_CLRBITS:
> +		local_irq_save(flags);
> +		/* Clear changeable bits with a 1 in arg. */
> +		shadow = *data_out[priv->minor];
> +		shadow &=  ~(arg & changeable_bits[priv->minor]);
> +		*data_out[priv->minor] = shadow;
> +		local_irq_restore(flags);
> +		break;
> +	case IO_HIGHALARM:
> +		/* Set alarm when bits with 1 in arg go high. */
> +		priv->highalarm |= arg;
> +		gpio_set_alarm(priv);
> +		break;
> +	case IO_LOWALARM:
> +		/* Set alarm when bits with 1 in arg go low. */
> +		priv->lowalarm |= arg;
> +		gpio_set_alarm(priv);
> +		break;
> +	case IO_CLRALARM:
> +		/* Clear alarm for bits with 1 in arg. */
> +		priv->highalarm &= ~arg;
> +		priv->lowalarm  &= ~arg;
> +		gpio_set_alarm(priv);
> +		break;
> +	case IO_READDIR: /* Use IO_SETGET_INPUT/OUTPUT instead! */
> +		/* Read direction 0=input 1=output */
> +		return *dir_oe[priv->minor];
> +	case IO_SETINPUT: /* Use IO_SETGET_INPUT instead! */
> +		/* Set direction 0=unchanged 1=input,
> +		 * return mask with 1=input
> +		 */
> +		return setget_input(priv, arg);
> +		break;
> +	case IO_SETOUTPUT: /* Use IO_SETGET_OUTPUT instead! */
> +		/* Set direction 0=unchanged 1=output,
> +		 * return mask with 1=output
> +		 */
> +		return setget_output(priv, arg);
> +
> +	case IO_CFG_WRITE_MODE:
> +	{
> +		unsigned long dir_shadow;
> +		dir_shadow = *dir_oe[priv->minor];
> +
> +		priv->clk_mask = arg & 0xFF;
> +		priv->data_mask = (arg >> 8) & 0xFF;
> +		priv->write_msb = (arg >> 16) & 0x01;
> +		/* Check if we're allowed to change the bits and
> +		 * the direction is correct
> +		 */
> +		if (!((priv->clk_mask & changeable_bits[priv->minor]) &&
> +		      (priv->data_mask & changeable_bits[priv->minor]) &&
> +		      (priv->clk_mask & dir_shadow) &&
> +		      (priv->data_mask & dir_shadow))) {
> +			priv->clk_mask = 0;
> +			priv->data_mask = 0;
> +			return -EPERM;
> +		}
> +		break;
> +	}
> +	case IO_READ_INBITS:
> +		/* *arg is result of reading the input pins */
> +		val = *data_in[priv->minor];
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		return 0;
> +		break;
> +	case IO_READ_OUTBITS:
> +		 /* *arg is result of reading the output shadow */
> +		val = *data_out[priv->minor];
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		break;
> +	case IO_SETGET_INPUT:
> +		/* bits set in *arg is set to input,
> +		 * *arg updated with current input pins.
> +		 */
> +		if (copy_from_user(&val, (unsigned long *)arg, sizeof(val)))
> +			return -EFAULT;
> +		val = setget_input(priv, val);
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		break;
> +	case IO_SETGET_OUTPUT:
> +		/* bits set in *arg is set to output,
> +		 * *arg updated with current output pins.
> +		 */
> +		if (copy_from_user(&val, (unsigned long *)arg, sizeof(val)))
> +			return -EFAULT;
> +		val = setget_output(priv, val);
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		break;
> +	default:
> +		return -EINVAL;
> +	} /* switch */
> +
> +	return 0;
> +}
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +static int
> +virtual_gpio_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
> +{
> +	unsigned long flags;
> +	unsigned short val;
> +	unsigned short shadow;
> +	struct gpio_private *priv = (struct gpio_private *)file->private_data;
> +
> +	switch (_IOC_NR(cmd)) {
> +	case IO_SETBITS:
> +		local_irq_save(flags);
> +		/* Set changeable bits with a 1 in arg. */
> +		i2c_read(VIRT_I2C_ADDR, (void *)&shadow, sizeof(shadow));
> +		shadow |= ~*dir_oe[priv->minor];
> +		shadow |= (arg & changeable_bits[priv->minor]);
> +		i2c_write(VIRT_I2C_ADDR, (void *)&shadow, sizeof(shadow));
> +		local_irq_restore(flags);
> +		break;
> +	case IO_CLRBITS:
> +		local_irq_save(flags);
> +		/* Clear changeable bits with a 1 in arg. */
> +		i2c_read(VIRT_I2C_ADDR, (void *)&shadow, sizeof(shadow));
> +		shadow |= ~*dir_oe[priv->minor];
> +		shadow &= ~(arg & changeable_bits[priv->minor]);
> +		i2c_write(VIRT_I2C_ADDR, (void *)&shadow, sizeof(shadow));
> +		local_irq_restore(flags);
> +		break;
> +	case IO_HIGHALARM:
> +		/* Set alarm when bits with 1 in arg go high. */
> +		priv->highalarm |= arg;
> +		break;
> +	case IO_LOWALARM:
> +		/* Set alarm when bits with 1 in arg go low. */
> +		priv->lowalarm |= arg;
> +		break;
> +	case IO_CLRALARM:
> +		/* Clear alarm for bits with 1 in arg. */
> +		priv->highalarm &= ~arg;
> +		priv->lowalarm  &= ~arg;
> +		break;
> +	case IO_CFG_WRITE_MODE:
> +	{
> +		unsigned long dir_shadow;
> +		dir_shadow = *dir_oe[priv->minor];
> +
> +		priv->clk_mask = arg & 0xFF;
> +		priv->data_mask = (arg >> 8) & 0xFF;
> +		priv->write_msb = (arg >> 16) & 0x01;
> +		/* Check if we're allowed to change the bits and
> +		 * the direction is correct
> +		 */
> +		if (!((priv->clk_mask & changeable_bits[priv->minor]) &&
> +		      (priv->data_mask & changeable_bits[priv->minor]) &&
> +		      (priv->clk_mask & dir_shadow) &&
> +		      (priv->data_mask & dir_shadow))) {
> +			priv->clk_mask = 0;
> +			priv->data_mask = 0;
> +			return -EPERM;
> +		}
> +		break;
> +	}
> +	case IO_READ_INBITS:
> +		/* *arg is result of reading the input pins */
> +		val = cached_virtual_gpio_read;
> +		val &= ~*dir_oe[priv->minor];
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		return 0;
> +		break;
> +	case IO_READ_OUTBITS:
> +		 /* *arg is result of reading the output shadow */
> +		i2c_read(VIRT_I2C_ADDR, (void *)&val, sizeof(val));
> +		val &= *dir_oe[priv->minor];
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		break;
> +	case IO_SETGET_INPUT:
> +	{
> +		/* bits set in *arg is set to input,
> +		 * *arg updated with current input pins.
> +		 */
> +		unsigned short input_mask = ~*dir_oe[priv->minor];
> +		if (copy_from_user(&val, (unsigned long *)arg, sizeof(val)))
> +			return -EFAULT;
> +		val = setget_input(priv, val);
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		if ((input_mask & val) != input_mask) {
> +			/* Input pins changed. All ports desired as input
> +			 * should be set to logic 1.
> +			 */
> +			unsigned short change = input_mask ^ val;
> +			i2c_read(VIRT_I2C_ADDR, (void *)&shadow,
> +				sizeof(shadow));
> +			shadow &= ~change;
> +			shadow |= val;
> +			i2c_write(VIRT_I2C_ADDR, (void *)&shadow,
> +				sizeof(shadow));
> +		}
> +		break;
> +	}
> +	case IO_SETGET_OUTPUT:
> +		/* bits set in *arg is set to output,
> +		 * *arg updated with current output pins.
> +		 */
> +		if (copy_from_user(&val, (unsigned long *)arg, sizeof(val)))
> +			return -EFAULT;
> +		val = setget_output(priv, val);
> +		if (copy_to_user((unsigned long *)arg, &val, sizeof(val)))
> +			return -EFAULT;
> +		break;
> +	default:
> +		return -EINVAL;
> +	} /* switch */
> +	return 0;
> +}
> +#endif /* CONFIG_ETRAX_VIRTUAL_GPIO */
> +
> +static int
> +gpio_leds_ioctl(unsigned int cmd, unsigned long arg)
> +{
> +	unsigned char green;
> +	unsigned char red;
> +
> +	switch (_IOC_NR(cmd)) {
> +	case IO_LEDACTIVE_SET:
> +		green = ((unsigned char) arg) & 1;
> +		red   = (((unsigned char) arg) >> 1) & 1;
> +		LED_ACTIVE_SET_G(green);
> +		LED_ACTIVE_SET_R(red);
> +		break;
> +
> +	default:
> +		return -EINVAL;
> +	} /* switch */
> +
> +	return 0;
> +}
> +
> +static int gpio_pwm_set_mode(unsigned long arg, int pwm_port)
> +{
> +	int pinmux_pwm = pinmux_pwm0 + pwm_port;
> +	int mode;
> +	reg_gio_rw_pwm0_ctrl rw_pwm_ctrl = {
> +		.ccd_val = 0,
> +		.ccd_override = regk_gio_no,
> +		.mode = regk_gio_no
> +	};
> +	int allocstatus;
> +
> +	if (get_user(mode, &((struct io_pwm_set_mode *) arg)->mode))
> +		return -EFAULT;
> +	rw_pwm_ctrl.mode = mode;
> +	if (mode != PWM_OFF)
> +		allocstatus = crisv32_pinmux_alloc_fixed(pinmux_pwm);
> +	else
> +		allocstatus = crisv32_pinmux_dealloc_fixed(pinmux_pwm);
> +	if (allocstatus)
> +		return allocstatus;
> +	REG_WRITE(reg_gio_rw_pwm0_ctrl, REG_ADDR(gio, regi_gio, rw_pwm0_ctrl) +
> +		12 * pwm_port, rw_pwm_ctrl);
> +	return 0;
> +}
> +
> +static int gpio_pwm_set_period(unsigned long arg, int pwm_port)
> +{
> +	struct io_pwm_set_period periods;
> +	reg_gio_rw_pwm0_var rw_pwm_widths;
> +
> +	if (copy_from_user(&periods, (struct io_pwm_set_period *) arg,
> +			sizeof(periods)))
> +		return -EFAULT;
> +	if (periods.lo > 8191 || periods.hi > 8191)
> +		return -EINVAL;
> +	rw_pwm_widths.lo = periods.lo;
> +	rw_pwm_widths.hi = periods.hi;
> +	REG_WRITE(reg_gio_rw_pwm0_var, REG_ADDR(gio, regi_gio, rw_pwm0_var) +
> +		12 * pwm_port, rw_pwm_widths);
> +	return 0;
> +}
> +
> +static int gpio_pwm_set_duty(unsigned long arg, int pwm_port)
> +{
> +	unsigned int duty;
> +	reg_gio_rw_pwm0_data rw_pwm_duty;
> +
> +	if (get_user(duty, &((struct io_pwm_set_duty *) arg)->duty))
> +		return -EFAULT;
> +	if (duty > 255)
> +		return -EINVAL;
> +	rw_pwm_duty.data = duty;
> +	REG_WRITE(reg_gio_rw_pwm0_data, REG_ADDR(gio, regi_gio, rw_pwm0_data) +
> +		12 * pwm_port, rw_pwm_duty);
> +	return 0;
> +}
> +
> +static int
> +gpio_pwm_ioctl(struct gpio_private *priv, unsigned int cmd, unsigned long arg)
> +{
> +	int pwm_port = priv->minor - GPIO_MINOR_PWM0;
> +
> +	switch (_IOC_NR(cmd)) {
> +	case IO_PWM_SET_MODE:
> +		return gpio_pwm_set_mode(arg, pwm_port);
> +	case IO_PWM_SET_PERIOD:
> +		return gpio_pwm_set_period(arg, pwm_port);
> +	case IO_PWM_SET_DUTY:
> +		return gpio_pwm_set_duty(arg, pwm_port);
> +	default:
> +		return -EINVAL;
> +	}
> +	return 0;
> +}
> +
> +struct file_operations gpio_fops = {
> +	.owner       = THIS_MODULE,
> +	.poll        = gpio_poll,
> +	.ioctl       = gpio_ioctl,
> +	.write       = gpio_write,
> +	.open        = gpio_open,
> +	.release     = gpio_release,
> +};
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +static void
> +virtual_gpio_init(void)
> +{
> +	reg_gio_rw_intr_cfg intr_cfg;
> +	reg_gio_rw_intr_mask intr_mask;
> +	unsigned short shadow;
> +
> +	shadow = ~virtual_rw_pv_oe; /* Input ports should be set to logic 1 */
> +	shadow |= CONFIG_ETRAX_DEF_GIO_PV_OUT;
> +	i2c_write(VIRT_I2C_ADDR, (void *)&shadow, sizeof(shadow));
> +
> +	/* Set interrupt mask and on what state the interrupt shall trigger.
> +	 * For virtual gpio the interrupt shall trigger on logic '0'.
> +	 */
> +	intr_cfg = REG_RD(gio, regi_gio, rw_intr_cfg);
> +	intr_mask = REG_RD(gio, regi_gio, rw_intr_mask);
> +
> +	switch (CONFIG_ETRAX_VIRTUAL_GPIO_INTERRUPT_PA_PIN) {
> +	case 0:
> +		intr_cfg.pa0 = regk_gio_lo;
> +		intr_mask.pa0 = regk_gio_yes;
> +		break;
> +	case 1:
> +		intr_cfg.pa1 = regk_gio_lo;
> +		intr_mask.pa1 = regk_gio_yes;
> +		break;
> +	case 2:
> +		intr_cfg.pa2 = regk_gio_lo;
> +		intr_mask.pa2 = regk_gio_yes;
> +		break;
> +	case 3:
> +		intr_cfg.pa3 = regk_gio_lo;
> +		intr_mask.pa3 = regk_gio_yes;
> +		break;
> +	case 4:
> +		intr_cfg.pa4 = regk_gio_lo;
> +		intr_mask.pa4 = regk_gio_yes;
> +		break;
> +	case 5:
> +		intr_cfg.pa5 = regk_gio_lo;
> +		intr_mask.pa5 = regk_gio_yes;
> +		break;
> +	case 6:
> +		intr_cfg.pa6 = regk_gio_lo;
> +		intr_mask.pa6 = regk_gio_yes;
> +		break;
> +	case 7:
> +		intr_cfg.pa7 = regk_gio_lo;
> +		intr_mask.pa7 = regk_gio_yes;
> +		break;
> +	}
> +
> +	REG_WR(gio, regi_gio, rw_intr_cfg, intr_cfg);
> +	REG_WR(gio, regi_gio, rw_intr_mask, intr_mask);
> +}
> +#endif
> +
> +/* main driver initialization routine, called from mem.c */
> +
> +static __init int
> +gpio_init(void)
> +{
> +	int res;
> +
> +	/* do the formalities */
> +
> +	res = register_chrdev(GPIO_MAJOR, gpio_name, &gpio_fops);
> +	if (res < 0) {
> +		printk(KERN_ERR "gpio: couldn't get a major number.\n");
> +		return res;
> +	}
> +
> +	/* Clear all leds */
> +	LED_NETWORK_GRP0_SET(0);
> +	LED_NETWORK_GRP1_SET(0);
> +	LED_ACTIVE_SET(0);
> +	LED_DISK_READ(0);
> +	LED_DISK_WRITE(0);
> +
> +	printk(KERN_INFO "ETRAX FS GPIO driver v2.6, (c) 2003-2007 "
> +		"Axis Communications AB\n");
> +	if (request_irq(GIO_INTR_VECT, gpio_interrupt,
> +			IRQF_SHARED | IRQF_DISABLED, "gpio", &alarmlist))
> +		printk(KERN_ERR "err: irq for gpio\n");
> +
> +	/* No IRQs by default. */
> +	REG_WR_INT(gio, regi_gio, rw_intr_pins, 0);
> +
> +#ifdef CONFIG_ETRAX_VIRTUAL_GPIO
> +	virtual_gpio_init();
> +#endif
> +
> +	return res;
> +}
> +
> +/* this makes sure that gpio_init is called during kernel boot */
> +
> +module_init(gpio_init);
--
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