static int ot200_backlight_probe(struct platform_device *pdev)
{
struct backlight_device *bl;
struct ot200_backlight_data *data;
struct backlight_properties props;
int retval = 0;
/* request gpio */
if (devm_gpio_request(&pdev->dev, GPIO_DIMM,
"ot200 backlight dimmer") < 0) {
dev_err(&pdev->dev, "failed to request GPIO %d\n", GPIO_DIMM);
return -ENODEV;
}
/* request timer */
pwm_timer = cs5535_mfgpt_alloc_timer(7, MFGPT_DOMAIN_ANY);
if (!pwm_timer) {
dev_err(&pdev->dev, "MFGPT 7 not available\n");
return -ENODEV;
}
data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);
if (!data) {
retval = -ENOMEM;
goto error_devm_kzalloc;
}
/* setup gpio */
cs5535_gpio_set(GPIO_DIMM, GPIO_OUTPUT_ENABLE);
cs5535_gpio_set(GPIO_DIMM, GPIO_OUTPUT_AUX1);
/* setup timer */
cs5535_mfgpt_write(pwm_timer, MFGPT_REG_CMP1, 0);
cs5535_mfgpt_write(pwm_timer, MFGPT_REG_CMP2, MAX_COMP2);
cs5535_mfgpt_write(pwm_timer, MFGPT_REG_SETUP, PWM_SETUP);
data->current_brightness = 100;
props.max_brightness = 100;
props.brightness = 100;
props.type = BACKLIGHT_RAW;
bl = devm_backlight_device_register(&pdev->dev, dev_name(&pdev->dev),
&pdev->dev, data, &ot200_backlight_ops,
&props);
if (IS_ERR(bl)) {
dev_err(&pdev->dev, "failed to register backlight\n");
retval = PTR_ERR(bl);
goto error_devm_kzalloc;
}
platform_set_drvdata(pdev, bl);
return 0;
error_devm_kzalloc:
cs5535_mfgpt_free_timer(pwm_timer);
return retval;
}
static void chip_gpio_set(struct gpio_chip *chip, unsigned offset, int val)
{
if (val)
cs5535_gpio_set(offset, GPIO_OUTPUT_VAL);
else
cs5535_gpio_clear(offset, GPIO_OUTPUT_VAL);
}
static int dcon_read_status_xo_1(u8 *status)
{
*status = gpio_get_value(OLPC_GPIO_DCON_STAT0);
*status |= gpio_get_value(OLPC_GPIO_DCON_STAT1) << 1;
/* Clear the negative edge status for GPIO7 */
cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_STS);
return 0;
}
static u8 dcon_read_status_xo_1(void)
{
u8 status;
status = gpio_get_value(OLPC_GPIO_DCON_STAT0);
status |= gpio_get_value(OLPC_GPIO_DCON_STAT1) << 1;
/* Clear the negative edge status for GPIO7 */
cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_STS);
return status;
}
static void dcon_wiggle_xo_1(void)
{
int x;
/*
* According to HiMax, when powering the DCON up we should hold
* SMB_DATA high for 8 SMB_CLK cycles. This will force the DCON
* state machine to reset to a (sane) initial state. Mitch Bradley
* did some testing and discovered that holding for 16 SMB_CLK cycles
* worked a lot more reliably, so that's what we do here.
*
* According to the cs5536 spec, to set GPIO14 to SMB_CLK we must
* simultaneously set AUX1 IN/OUT to GPIO14; ditto for SMB_DATA and
* GPIO15.
*/
cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL);
cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_VAL);
cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_ENABLE);
cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_ENABLE);
cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX1);
cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX1);
cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX2);
cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX2);
cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_INPUT_AUX1);
cs5535_gpio_clear(OLPC_GPIO_SMB_DATA, GPIO_INPUT_AUX1);
for (x = 0; x < 16; x++) {
udelay(5);
cs5535_gpio_clear(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL);
udelay(5);
cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_VAL);
}
udelay(5);
cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_OUTPUT_AUX1);
cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_OUTPUT_AUX1);
cs5535_gpio_set(OLPC_GPIO_SMB_CLK, GPIO_INPUT_AUX1);
cs5535_gpio_set(OLPC_GPIO_SMB_DATA, GPIO_INPUT_AUX1);
}
static int dcon_init_xo_1(struct dcon_priv *dcon)
{
unsigned char lob;
if (gpio_request(OLPC_GPIO_DCON_STAT0, "OLPC-DCON")) {
printk(KERN_ERR "olpc-dcon: failed to request STAT0 GPIO\n");
return -EIO;
}
if (gpio_request(OLPC_GPIO_DCON_STAT1, "OLPC-DCON")) {
printk(KERN_ERR "olpc-dcon: failed to request STAT1 GPIO\n");
goto err_gp_stat1;
}
if (gpio_request(OLPC_GPIO_DCON_IRQ, "OLPC-DCON")) {
printk(KERN_ERR "olpc-dcon: failed to request IRQ GPIO\n");
goto err_gp_irq;
}
if (gpio_request(OLPC_GPIO_DCON_LOAD, "OLPC-DCON")) {
printk(KERN_ERR "olpc-dcon: failed to request LOAD GPIO\n");
goto err_gp_load;
}
if (gpio_request(OLPC_GPIO_DCON_BLANK, "OLPC-DCON")) {
printk(KERN_ERR "olpc-dcon: failed to request BLANK GPIO\n");
goto err_gp_blank;
}
/* Turn off the event enable for GPIO7 just to be safe */
cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_EVENTS_ENABLE);
/*
* Determine the current state by reading the GPIO bit; earlier
* stages of the boot process have established the state.
*
* Note that we read GPIO_OUPUT_VAL rather than GPIO_READ_BACK here;
* this is because OFW will disable input for the pin and set a value..
* READ_BACK will only contain a valid value if input is enabled and
* then a value is set. So, future readings of the pin can use
* READ_BACK, but the first one cannot. Awesome, huh?
*/
dcon->curr_src = cs5535_gpio_isset(OLPC_GPIO_DCON_LOAD, GPIO_OUTPUT_VAL)
? DCON_SOURCE_CPU
: DCON_SOURCE_DCON;
dcon->pending_src = dcon->curr_src;
/* Set the directions for the GPIO pins */
gpio_direction_input(OLPC_GPIO_DCON_STAT0);
gpio_direction_input(OLPC_GPIO_DCON_STAT1);
gpio_direction_input(OLPC_GPIO_DCON_IRQ);
gpio_direction_input(OLPC_GPIO_DCON_BLANK);
gpio_direction_output(OLPC_GPIO_DCON_LOAD,
dcon->curr_src == DCON_SOURCE_CPU);
/* Set up the interrupt mappings */
/* Set the IRQ to pair 2 */
cs5535_gpio_setup_event(OLPC_GPIO_DCON_IRQ, 2, 0);
/* Enable group 2 to trigger the DCON interrupt */
cs5535_gpio_set_irq(2, DCON_IRQ);
/* Select edge level for interrupt (in PIC) */
lob = inb(0x4d0);
lob &= ~(1 << DCON_IRQ);
outb(lob, 0x4d0);
/* Register the interrupt handler */
if (request_irq(DCON_IRQ, &dcon_interrupt, 0, "DCON", dcon)) {
printk(KERN_ERR "olpc-dcon: failed to request DCON's irq\n");
goto err_req_irq;
}
/* Clear INV_EN for GPIO7 (DCONIRQ) */
cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_INVERT);
/* Enable filter for GPIO12 (DCONBLANK) */
cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_INPUT_FILTER);
/* Disable filter for GPIO7 */
cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_FILTER);
/* Disable event counter for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */
cs5535_gpio_clear(OLPC_GPIO_DCON_IRQ, GPIO_INPUT_EVENT_COUNT);
cs5535_gpio_clear(OLPC_GPIO_DCON_BLANK, GPIO_INPUT_EVENT_COUNT);
/* Add GPIO12 to the Filter Event Pair #7 */
cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_FE7_SEL);
/* Turn off negative Edge Enable for GPIO12 */
cs5535_gpio_clear(OLPC_GPIO_DCON_BLANK, GPIO_NEGATIVE_EDGE_EN);
/* Enable negative Edge Enable for GPIO7 */
cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_EN);
/* Zero the filter amount for Filter Event Pair #7 */
cs5535_gpio_set(0, GPIO_FLTR7_AMOUNT);
/* Clear the negative edge status for GPIO7 and GPIO12 */
cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_NEGATIVE_EDGE_STS);
cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_NEGATIVE_EDGE_STS);
/* FIXME: Clear the positive status as well, just to be sure */
cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_POSITIVE_EDGE_STS);
cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_POSITIVE_EDGE_STS);
/* Enable events for GPIO7 (DCONIRQ) and GPIO12 (DCONBLANK) */
cs5535_gpio_set(OLPC_GPIO_DCON_IRQ, GPIO_EVENTS_ENABLE);
cs5535_gpio_set(OLPC_GPIO_DCON_BLANK, GPIO_EVENTS_ENABLE);
return 0;
err_req_irq:
gpio_free(OLPC_GPIO_DCON_BLANK);
err_gp_blank:
gpio_free(OLPC_GPIO_DCON_LOAD);
err_gp_load:
gpio_free(OLPC_GPIO_DCON_IRQ);
err_gp_irq:
gpio_free(OLPC_GPIO_DCON_STAT1);
err_gp_stat1:
gpio_free(OLPC_GPIO_DCON_STAT0);
return -EIO;
}