ASIC3 driver
This is a patch for the Compaq ASIC3 multi function chip, found in many
PDAs (iPAQs, HTCs...).
It is a simplified version of Paul Sokolovsky's first proposal [1]. With
this code, it is basically a GPIO and IRQ expander. My plan is to add more
features once this patch gets reviewed and accepted.
[1] http://lkml.org/lkml/2007/5/1/46
Signed-off-by: Samuel Ortiz <sameo@openedhand.com>
Cc: Paul Sokolovsky <pmiscml@gmail.com>
Cc: Ben Dooks <ben@trinity.fluff.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/mfd/asic3.c b/drivers/mfd/asic3.c
new file mode 100644
index 0000000..63fb1ff3
--- /dev/null
+++ b/drivers/mfd/asic3.c
@@ -0,0 +1,588 @@
+/*
+ * driver/mfd/asic3.c
+ *
+ * Compaq ASIC3 support.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Copyright 2001 Compaq Computer Corporation.
+ * Copyright 2004-2005 Phil Blundell
+ * Copyright 2007 OpenedHand Ltd.
+ *
+ * Authors: Phil Blundell <pb@handhelds.org>,
+ * Samuel Ortiz <sameo@openedhand.com>
+ *
+ */
+
+#include <linux/version.h>
+#include <linux/kernel.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/platform_device.h>
+
+#include <linux/mfd/asic3.h>
+
+static inline void asic3_write_register(struct asic3 *asic,
+ unsigned int reg, u32 value)
+{
+ iowrite16(value, (unsigned long)asic->mapping +
+ (reg >> asic->bus_shift));
+}
+
+static inline u32 asic3_read_register(struct asic3 *asic,
+ unsigned int reg)
+{
+ return ioread16((unsigned long)asic->mapping +
+ (reg >> asic->bus_shift));
+}
+
+/* IRQs */
+#define MAX_ASIC_ISR_LOOPS 20
+#define ASIC3_GPIO_Base_INCR \
+ (ASIC3_GPIO_B_Base - ASIC3_GPIO_A_Base)
+
+static void asic3_irq_flip_edge(struct asic3 *asic,
+ u32 base, int bit)
+{
+ u16 edge;
+ unsigned long flags;
+
+ spin_lock_irqsave(&asic->lock, flags);
+ edge = asic3_read_register(asic,
+ base + ASIC3_GPIO_EdgeTrigger);
+ edge ^= bit;
+ asic3_write_register(asic,
+ base + ASIC3_GPIO_EdgeTrigger, edge);
+ spin_unlock_irqrestore(&asic->lock, flags);
+}
+
+static void asic3_irq_demux(unsigned int irq, struct irq_desc *desc)
+{
+ int iter, i;
+ unsigned long flags;
+ struct asic3 *asic;
+
+ desc->chip->ack(irq);
+
+ asic = desc->handler_data;
+
+ for (iter = 0 ; iter < MAX_ASIC_ISR_LOOPS; iter++) {
+ u32 status;
+ int bank;
+
+ spin_lock_irqsave(&asic->lock, flags);
+ status = asic3_read_register(asic,
+ ASIC3_OFFSET(INTR, PIntStat));
+ spin_unlock_irqrestore(&asic->lock, flags);
+
+ /* Check all ten register bits */
+ if ((status & 0x3ff) == 0)
+ break;
+
+ /* Handle GPIO IRQs */
+ for (bank = 0; bank < ASIC3_NUM_GPIO_BANKS; bank++) {
+ if (status & (1 << bank)) {
+ unsigned long base, istat;
+
+ base = ASIC3_GPIO_A_Base
+ + bank * ASIC3_GPIO_Base_INCR;
+
+ spin_lock_irqsave(&asic->lock, flags);
+ istat = asic3_read_register(asic,
+ base +
+ ASIC3_GPIO_IntStatus);
+ /* Clearing IntStatus */
+ asic3_write_register(asic,
+ base +
+ ASIC3_GPIO_IntStatus, 0);
+ spin_unlock_irqrestore(&asic->lock, flags);
+
+ for (i = 0; i < ASIC3_GPIOS_PER_BANK; i++) {
+ int bit = (1 << i);
+ unsigned int irqnr;
+
+ if (!(istat & bit))
+ continue;
+
+ irqnr = asic->irq_base +
+ (ASIC3_GPIOS_PER_BANK * bank)
+ + i;
+ desc = irq_desc + irqnr;
+ desc->handle_irq(irqnr, desc);
+ if (asic->irq_bothedge[bank] & bit)
+ asic3_irq_flip_edge(asic, base,
+ bit);
+ }
+ }
+ }
+
+ /* Handle remaining IRQs in the status register */
+ for (i = ASIC3_NUM_GPIOS; i < ASIC3_NR_IRQS; i++) {
+ /* They start at bit 4 and go up */
+ if (status & (1 << (i - ASIC3_NUM_GPIOS + 4))) {
+ desc = irq_desc + + i;
+ desc->handle_irq(asic->irq_base + i,
+ desc);
+ }
+ }
+ }
+
+ if (iter >= MAX_ASIC_ISR_LOOPS)
+ printk(KERN_ERR "%s: interrupt processing overrun\n",
+ __FUNCTION__);
+}
+
+static inline int asic3_irq_to_bank(struct asic3 *asic, int irq)
+{
+ int n;
+
+ n = (irq - asic->irq_base) >> 4;
+
+ return (n * (ASIC3_GPIO_B_Base - ASIC3_GPIO_A_Base));
+}
+
+static inline int asic3_irq_to_index(struct asic3 *asic, int irq)
+{
+ return (irq - asic->irq_base) & 0xf;
+}
+
+static void asic3_mask_gpio_irq(unsigned int irq)
+{
+ struct asic3 *asic = get_irq_chip_data(irq);
+ u32 val, bank, index;
+ unsigned long flags;
+
+ bank = asic3_irq_to_bank(asic, irq);
+ index = asic3_irq_to_index(asic, irq);
+
+ spin_lock_irqsave(&asic->lock, flags);
+ val = asic3_read_register(asic, bank + ASIC3_GPIO_Mask);
+ val |= 1 << index;
+ asic3_write_register(asic, bank + ASIC3_GPIO_Mask, val);
+ spin_unlock_irqrestore(&asic->lock, flags);
+}
+
+static void asic3_mask_irq(unsigned int irq)
+{
+ struct asic3 *asic = get_irq_chip_data(irq);
+ int regval;
+ unsigned long flags;
+
+ spin_lock_irqsave(&asic->lock, flags);
+ regval = asic3_read_register(asic,
+ ASIC3_INTR_Base +
+ ASIC3_INTR_IntMask);
+
+ regval &= ~(ASIC3_INTMASK_MASK0 <<
+ (irq - (asic->irq_base + ASIC3_NUM_GPIOS)));
+
+ asic3_write_register(asic,
+ ASIC3_INTR_Base +
+ ASIC3_INTR_IntMask,
+ regval);
+ spin_unlock_irqrestore(&asic->lock, flags);
+}
+
+static void asic3_unmask_gpio_irq(unsigned int irq)
+{
+ struct asic3 *asic = get_irq_chip_data(irq);
+ u32 val, bank, index;
+ unsigned long flags;
+
+ bank = asic3_irq_to_bank(asic, irq);
+ index = asic3_irq_to_index(asic, irq);
+
+ spin_lock_irqsave(&asic->lock, flags);
+ val = asic3_read_register(asic, bank + ASIC3_GPIO_Mask);
+ val &= ~(1 << index);
+ asic3_write_register(asic, bank + ASIC3_GPIO_Mask, val);
+ spin_unlock_irqrestore(&asic->lock, flags);
+}
+
+static void asic3_unmask_irq(unsigned int irq)
+{
+ struct asic3 *asic = get_irq_chip_data(irq);
+ int regval;
+ unsigned long flags;
+
+ spin_lock_irqsave(&asic->lock, flags);
+ regval = asic3_read_register(asic,
+ ASIC3_INTR_Base +
+ ASIC3_INTR_IntMask);
+
+ regval |= (ASIC3_INTMASK_MASK0 <<
+ (irq - (asic->irq_base + ASIC3_NUM_GPIOS)));
+
+ asic3_write_register(asic,
+ ASIC3_INTR_Base +
+ ASIC3_INTR_IntMask,
+ regval);
+ spin_unlock_irqrestore(&asic->lock, flags);
+}
+
+static int asic3_gpio_irq_type(unsigned int irq, unsigned int type)
+{
+ struct asic3 *asic = get_irq_chip_data(irq);
+ u32 bank, index;
+ u16 trigger, level, edge, bit;
+ unsigned long flags;
+
+ bank = asic3_irq_to_bank(asic, irq);
+ index = asic3_irq_to_index(asic, irq);
+ bit = 1<<index;
+
+ spin_lock_irqsave(&asic->lock, flags);
+ level = asic3_read_register(asic,
+ bank + ASIC3_GPIO_LevelTrigger);
+ edge = asic3_read_register(asic,
+ bank + ASIC3_GPIO_EdgeTrigger);
+ trigger = asic3_read_register(asic,
+ bank + ASIC3_GPIO_TriggerType);
+ asic->irq_bothedge[(irq - asic->irq_base) >> 4] &= ~bit;
+
+ if (type == IRQT_RISING) {
+ trigger |= bit;
+ edge |= bit;
+ } else if (type == IRQT_FALLING) {
+ trigger |= bit;
+ edge &= ~bit;
+ } else if (type == IRQT_BOTHEDGE) {
+ trigger |= bit;
+ if (asic3_gpio_get_value(asic, irq - asic->irq_base))
+ edge &= ~bit;
+ else
+ edge |= bit;
+ asic->irq_bothedge[(irq - asic->irq_base) >> 4] |= bit;
+ } else if (type == IRQT_LOW) {
+ trigger &= ~bit;
+ level &= ~bit;
+ } else if (type == IRQT_HIGH) {
+ trigger &= ~bit;
+ level |= bit;
+ } else {
+ /*
+ * if type == IRQT_NOEDGE, we should mask interrupts, but
+ * be careful to not unmask them if mask was also called.
+ * Probably need internal state for mask.
+ */
+ printk(KERN_NOTICE "asic3: irq type not changed.\n");
+ }
+ asic3_write_register(asic, bank + ASIC3_GPIO_LevelTrigger,
+ level);
+ asic3_write_register(asic, bank + ASIC3_GPIO_EdgeTrigger,
+ edge);
+ asic3_write_register(asic, bank + ASIC3_GPIO_TriggerType,
+ trigger);
+ spin_unlock_irqrestore(&asic->lock, flags);
+ return 0;
+}
+
+static struct irq_chip asic3_gpio_irq_chip = {
+ .name = "ASIC3-GPIO",
+ .ack = asic3_mask_gpio_irq,
+ .mask = asic3_mask_gpio_irq,
+ .unmask = asic3_unmask_gpio_irq,
+ .set_type = asic3_gpio_irq_type,
+};
+
+static struct irq_chip asic3_irq_chip = {
+ .name = "ASIC3",
+ .ack = asic3_mask_irq,
+ .mask = asic3_mask_irq,
+ .unmask = asic3_unmask_irq,
+};
+
+static int asic3_irq_probe(struct platform_device *pdev)
+{
+ struct asic3 *asic = platform_get_drvdata(pdev);
+ unsigned long clksel = 0;
+ unsigned int irq, irq_base;
+
+ asic->irq_nr = platform_get_irq(pdev, 0);
+ if (asic->irq_nr < 0)
+ return asic->irq_nr;
+
+ /* turn on clock to IRQ controller */
+ clksel |= CLOCK_SEL_CX;
+ asic3_write_register(asic, ASIC3_OFFSET(CLOCK, SEL),
+ clksel);
+
+ irq_base = asic->irq_base;
+
+ for (irq = irq_base; irq < irq_base + ASIC3_NR_IRQS; irq++) {
+ if (irq < asic->irq_base + ASIC3_NUM_GPIOS)
+ set_irq_chip(irq, &asic3_gpio_irq_chip);
+ else
+ set_irq_chip(irq, &asic3_irq_chip);
+
+ set_irq_chip_data(irq, asic);
+ set_irq_handler(irq, handle_level_irq);
+ set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+ }
+
+ asic3_write_register(asic, ASIC3_OFFSET(INTR, IntMask),
+ ASIC3_INTMASK_GINTMASK);
+
+ set_irq_chained_handler(asic->irq_nr, asic3_irq_demux);
+ set_irq_type(asic->irq_nr, IRQT_RISING);
+ set_irq_data(asic->irq_nr, asic);
+
+ return 0;
+}
+
+static void asic3_irq_remove(struct platform_device *pdev)
+{
+ struct asic3 *asic = platform_get_drvdata(pdev);
+ unsigned int irq, irq_base;
+
+ irq_base = asic->irq_base;
+
+ for (irq = irq_base; irq < irq_base + ASIC3_NR_IRQS; irq++) {
+ set_irq_flags(irq, 0);
+ set_irq_handler(irq, NULL);
+ set_irq_chip(irq, NULL);
+ set_irq_chip_data(irq, NULL);
+ }
+ set_irq_chained_handler(asic->irq_nr, NULL);
+}
+
+/* GPIOs */
+static inline u32 asic3_get_gpio(struct asic3 *asic, unsigned int base,
+ unsigned int function)
+{
+ return asic3_read_register(asic, base + function);
+}
+
+static void asic3_set_gpio(struct asic3 *asic, unsigned int base,
+ unsigned int function, u32 bits, u32 val)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&asic->lock, flags);
+ val |= (asic3_read_register(asic, base + function) & ~bits);
+
+ asic3_write_register(asic, base + function, val);
+ spin_unlock_irqrestore(&asic->lock, flags);
+}
+
+#define asic3_get_gpio_a(asic, fn) \
+ asic3_get_gpio(asic, ASIC3_GPIO_A_Base, ASIC3_GPIO_##fn)
+#define asic3_get_gpio_b(asic, fn) \
+ asic3_get_gpio(asic, ASIC3_GPIO_B_Base, ASIC3_GPIO_##fn)
+#define asic3_get_gpio_c(asic, fn) \
+ asic3_get_gpio(asic, ASIC3_GPIO_C_Base, ASIC3_GPIO_##fn)
+#define asic3_get_gpio_d(asic, fn) \
+ asic3_get_gpio(asic, ASIC3_GPIO_D_Base, ASIC3_GPIO_##fn)
+
+#define asic3_set_gpio_a(asic, fn, bits, val) \
+ asic3_set_gpio(asic, ASIC3_GPIO_A_Base, ASIC3_GPIO_##fn, bits, val)
+#define asic3_set_gpio_b(asic, fn, bits, val) \
+ asic3_set_gpio(asic, ASIC3_GPIO_B_Base, ASIC3_GPIO_##fn, bits, val)
+#define asic3_set_gpio_c(asic, fn, bits, val) \
+ asic3_set_gpio(asic, ASIC3_GPIO_C_Base, ASIC3_GPIO_##fn, bits, val)
+#define asic3_set_gpio_d(asic, fn, bits, val) \
+ asic3_set_gpio(asic, ASIC3_GPIO_D_Base, ASIC3_GPIO_##fn, bits, val)
+
+#define asic3_set_gpio_banks(asic, fn, bits, pdata, field) \
+ do { \
+ asic3_set_gpio_a((asic), fn, (bits), (pdata)->gpio_a.field); \
+ asic3_set_gpio_b((asic), fn, (bits), (pdata)->gpio_b.field); \
+ asic3_set_gpio_c((asic), fn, (bits), (pdata)->gpio_c.field); \
+ asic3_set_gpio_d((asic), fn, (bits), (pdata)->gpio_d.field); \
+ } while (0)
+
+int asic3_gpio_get_value(struct asic3 *asic, unsigned gpio)
+{
+ u32 mask = ASIC3_GPIO_bit(gpio);
+
+ switch (gpio >> 4) {
+ case ASIC3_GPIO_BANK_A:
+ return asic3_get_gpio_a(asic, Status) & mask;
+ case ASIC3_GPIO_BANK_B:
+ return asic3_get_gpio_b(asic, Status) & mask;
+ case ASIC3_GPIO_BANK_C:
+ return asic3_get_gpio_c(asic, Status) & mask;
+ case ASIC3_GPIO_BANK_D:
+ return asic3_get_gpio_d(asic, Status) & mask;
+ default:
+ printk(KERN_ERR "%s: invalid GPIO value 0x%x",
+ __FUNCTION__, gpio);
+ return -EINVAL;
+ }
+}
+EXPORT_SYMBOL(asic3_gpio_get_value);
+
+void asic3_gpio_set_value(struct asic3 *asic, unsigned gpio, int val)
+{
+ u32 mask = ASIC3_GPIO_bit(gpio);
+ u32 bitval = 0;
+ if (val)
+ bitval = mask;
+
+ switch (gpio >> 4) {
+ case ASIC3_GPIO_BANK_A:
+ asic3_set_gpio_a(asic, Out, mask, bitval);
+ return;
+ case ASIC3_GPIO_BANK_B:
+ asic3_set_gpio_b(asic, Out, mask, bitval);
+ return;
+ case ASIC3_GPIO_BANK_C:
+ asic3_set_gpio_c(asic, Out, mask, bitval);
+ return;
+ case ASIC3_GPIO_BANK_D:
+ asic3_set_gpio_d(asic, Out, mask, bitval);
+ return;
+ default:
+ printk(KERN_ERR "%s: invalid GPIO value 0x%x",
+ __FUNCTION__, gpio);
+ return;
+ }
+}
+EXPORT_SYMBOL(asic3_gpio_set_value);
+
+static int asic3_gpio_probe(struct platform_device *pdev)
+{
+ struct asic3_platform_data *pdata = pdev->dev.platform_data;
+ struct asic3 *asic = platform_get_drvdata(pdev);
+
+ asic3_write_register(asic, ASIC3_GPIO_OFFSET(A, Mask), 0xffff);
+ asic3_write_register(asic, ASIC3_GPIO_OFFSET(B, Mask), 0xffff);
+ asic3_write_register(asic, ASIC3_GPIO_OFFSET(C, Mask), 0xffff);
+ asic3_write_register(asic, ASIC3_GPIO_OFFSET(D, Mask), 0xffff);
+
+ asic3_set_gpio_a(asic, SleepMask, 0xffff, 0xffff);
+ asic3_set_gpio_b(asic, SleepMask, 0xffff, 0xffff);
+ asic3_set_gpio_c(asic, SleepMask, 0xffff, 0xffff);
+ asic3_set_gpio_d(asic, SleepMask, 0xffff, 0xffff);
+
+ if (pdata) {
+ asic3_set_gpio_banks(asic, Out, 0xffff, pdata, init);
+ asic3_set_gpio_banks(asic, Direction, 0xffff, pdata, dir);
+ asic3_set_gpio_banks(asic, SleepMask, 0xffff, pdata,
+ sleep_mask);
+ asic3_set_gpio_banks(asic, SleepOut, 0xffff, pdata, sleep_out);
+ asic3_set_gpio_banks(asic, BattFaultOut, 0xffff, pdata,
+ batt_fault_out);
+ asic3_set_gpio_banks(asic, SleepConf, 0xffff, pdata,
+ sleep_conf);
+ asic3_set_gpio_banks(asic, AltFunction, 0xffff, pdata,
+ alt_function);
+ }
+
+ return 0;
+}
+
+static void asic3_gpio_remove(struct platform_device *pdev)
+{
+ return;
+}
+
+
+/* Core */
+static int asic3_probe(struct platform_device *pdev)
+{
+ struct asic3_platform_data *pdata = pdev->dev.platform_data;
+ struct asic3 *asic;
+ struct resource *mem;
+ unsigned long clksel;
+ int ret;
+
+ asic = kzalloc(sizeof(struct asic3), GFP_KERNEL);
+ if (!asic)
+ return -ENOMEM;
+
+ spin_lock_init(&asic->lock);
+ platform_set_drvdata(pdev, asic);
+ asic->dev = &pdev->dev;
+
+ mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!mem) {
+ ret = -ENOMEM;
+ printk(KERN_ERR "asic3: no MEM resource\n");
+ goto err_out_1;
+ }
+
+ asic->mapping = ioremap(mem->start, PAGE_SIZE);
+ if (!asic->mapping) {
+ ret = -ENOMEM;
+ printk(KERN_ERR "asic3: couldn't ioremap\n");
+ goto err_out_1;
+ }
+
+ asic->irq_base = pdata->irq_base;
+
+ if (pdata && pdata->bus_shift)
+ asic->bus_shift = 2 - pdata->bus_shift;
+ else
+ asic->bus_shift = 0;
+
+ clksel = 0;
+ asic3_write_register(asic, ASIC3_OFFSET(CLOCK, SEL), clksel);
+
+ ret = asic3_irq_probe(pdev);
+ if (ret < 0) {
+ printk(KERN_ERR "asic3: couldn't probe IRQs\n");
+ goto err_out_2;
+ }
+ asic3_gpio_probe(pdev);
+
+ if (pdata->children) {
+ int i;
+ for (i = 0; i < pdata->n_children; i++) {
+ pdata->children[i]->dev.parent = &pdev->dev;
+ platform_device_register(pdata->children[i]);
+ }
+ }
+
+ printk(KERN_INFO "ASIC3 Core driver\n");
+
+ return 0;
+
+ err_out_2:
+ iounmap(asic->mapping);
+ err_out_1:
+ kfree(asic);
+
+ return ret;
+}
+
+static int asic3_remove(struct platform_device *pdev)
+{
+ struct asic3 *asic = platform_get_drvdata(pdev);
+
+ asic3_gpio_remove(pdev);
+ asic3_irq_remove(pdev);
+
+ asic3_write_register(asic, ASIC3_OFFSET(CLOCK, SEL), 0);
+
+ iounmap(asic->mapping);
+
+ kfree(asic);
+
+ return 0;
+}
+
+static void asic3_shutdown(struct platform_device *pdev)
+{
+}
+
+static struct platform_driver asic3_device_driver = {
+ .driver = {
+ .name = "asic3",
+ },
+ .probe = asic3_probe,
+ .remove = __devexit_p(asic3_remove),
+ .shutdown = asic3_shutdown,
+};
+
+static int __init asic3_init(void)
+{
+ int retval = 0;
+ retval = platform_driver_register(&asic3_device_driver);
+ return retval;
+}
+
+subsys_initcall(asic3_init);