diff options
Diffstat (limited to 'drivers/char/pc8736x_gpio.c')
| -rw-r--r-- | drivers/char/pc8736x_gpio.c | 27 |
1 files changed, 23 insertions, 4 deletions
diff --git a/drivers/char/pc8736x_gpio.c b/drivers/char/pc8736x_gpio.c index 48ff1fc8b06d..b8183d508332 100644 --- a/drivers/char/pc8736x_gpio.c +++ b/drivers/char/pc8736x_gpio.c @@ -33,6 +33,7 @@ MODULE_PARM_DESC(major, "Major device number"); static DEFINE_SPINLOCK(pc8736x_gpio_config_lock); static unsigned pc8736x_gpio_base; +static u8 pc8736x_gpio_shadow[4]; #define SIO_BASE1 0x2E /* 1st command-reg to check */ #define SIO_BASE2 0x4E /* alt command-reg to check */ @@ -184,6 +185,7 @@ static void pc8736x_gpio_set(unsigned minor, int val) val = inb_p(pc8736x_gpio_base + port_offset[port] + PORT_IN); dev_dbg(&pdev->dev, "wrote %x, read: %x\n", curval, val); + pc8736x_gpio_shadow[port] = val; } static void pc8736x_gpio_set_high(unsigned index) @@ -196,15 +198,18 @@ static void pc8736x_gpio_set_low(unsigned index) pc8736x_gpio_set(index, 0); } -static int pc8736x_gpio_current(unsigned index) +static int pc8736x_gpio_current(unsigned minor) { - dev_warn(&pdev->dev, "pc8736x_gpio_current unimplemented\n"); - return 0; + int port, bit; + minor &= 0x1f; + port = minor >> 3; + bit = minor & 7; + return ((pc8736x_gpio_shadow[port] >> bit) & 0x01); } static void pc8736x_gpio_change(unsigned index) { - pc8736x_gpio_set(index, !pc8736x_gpio_get(index)); + pc8736x_gpio_set(index, !pc8736x_gpio_current(index)); } static struct nsc_gpio_ops pc8736x_access = { @@ -238,6 +243,18 @@ static struct file_operations pc8736x_gpio_fops = { .read = nsc_gpio_read, }; +static void __init pc8736x_init_shadow(void) +{ + int port; + + /* read the current values driven on the GPIO signals */ + for (port = 0; port < 4; ++port) + pc8736x_gpio_shadow[port] + = inb_p(pc8736x_gpio_base + port_offset[port] + + PORT_OUT); + +} + static int __init pc8736x_gpio_init(void) { int rc = 0; @@ -317,5 +334,7 @@ static void __exit pc8736x_gpio_cleanup(void) unregister_chrdev(major, DEVNAME); } +EXPORT_SYMBOL(pc8736x_access); + module_init(pc8736x_gpio_init); module_exit(pc8736x_gpio_cleanup); |