mfd: pm8xxx: Move pm8xxx-irq.c contents into only driver that uses it

The pm8xxx-irq.c code is practically mandatory given that the
pm8921-core driver will WARN about it missing and the Kconfig
marks it as default y when a PM8xxx chips is enabled. The only
reason the file was split out was because we planned to support
other pm8xxx chips with different pm8xxx-core.c files. Now that
we have DT on ARM this isn't necessary because we should be able
to support all the ssbi based PM8xxx chips in one driver and one
file with no data bloat. Let's move this code into the only
driver that uses it right now (pm8921) so that it's always compiled when
needed. In the future we can rename pm8921-core.c to something
more generic.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/pm8921-core.c b/drivers/mfd/pm8921-core.c
index 484fe66..50e0a9b 100644
--- a/drivers/mfd/pm8921-core.c
+++ b/drivers/mfd/pm8921-core.c
@@ -14,6 +14,8 @@
 #define pr_fmt(fmt) "%s: " fmt, __func__
 
 #include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/slab.h>
@@ -22,15 +24,361 @@
 #include <linux/mfd/core.h>
 #include <linux/mfd/pm8xxx/pm8921.h>
 #include <linux/mfd/pm8xxx/core.h>
+#include <linux/mfd/pm8xxx/irq.h>
+
+#define	SSBI_REG_ADDR_IRQ_BASE		0x1BB
+
+#define	SSBI_REG_ADDR_IRQ_ROOT		(SSBI_REG_ADDR_IRQ_BASE + 0)
+#define	SSBI_REG_ADDR_IRQ_M_STATUS1	(SSBI_REG_ADDR_IRQ_BASE + 1)
+#define	SSBI_REG_ADDR_IRQ_M_STATUS2	(SSBI_REG_ADDR_IRQ_BASE + 2)
+#define	SSBI_REG_ADDR_IRQ_M_STATUS3	(SSBI_REG_ADDR_IRQ_BASE + 3)
+#define	SSBI_REG_ADDR_IRQ_M_STATUS4	(SSBI_REG_ADDR_IRQ_BASE + 4)
+#define	SSBI_REG_ADDR_IRQ_BLK_SEL	(SSBI_REG_ADDR_IRQ_BASE + 5)
+#define	SSBI_REG_ADDR_IRQ_IT_STATUS	(SSBI_REG_ADDR_IRQ_BASE + 6)
+#define	SSBI_REG_ADDR_IRQ_CONFIG	(SSBI_REG_ADDR_IRQ_BASE + 7)
+#define	SSBI_REG_ADDR_IRQ_RT_STATUS	(SSBI_REG_ADDR_IRQ_BASE + 8)
+
+#define	PM_IRQF_LVL_SEL			0x01	/* level select */
+#define	PM_IRQF_MASK_FE			0x02	/* mask falling edge */
+#define	PM_IRQF_MASK_RE			0x04	/* mask rising edge */
+#define	PM_IRQF_CLR			0x08	/* clear interrupt */
+#define	PM_IRQF_BITS_MASK		0x70
+#define	PM_IRQF_BITS_SHIFT		4
+#define	PM_IRQF_WRITE			0x80
+
+#define	PM_IRQF_MASK_ALL		(PM_IRQF_MASK_FE | \
+					PM_IRQF_MASK_RE)
 
 #define REG_HWREV		0x002  /* PMIC4 revision */
 #define REG_HWREV_2		0x0E8  /* PMIC4 revision 2 */
 
+struct pm_irq_chip {
+	struct device		*dev;
+	spinlock_t		pm_irq_lock;
+	unsigned int		devirq;
+	unsigned int		irq_base;
+	unsigned int		num_irqs;
+	unsigned int		num_blocks;
+	unsigned int		num_masters;
+	u8			config[0];
+};
+
 struct pm8921 {
 	struct device			*dev;
 	struct pm_irq_chip		*irq_chip;
 };
 
+static int pm8xxx_read_root_irq(const struct pm_irq_chip *chip, u8 *rp)
+{
+	return pm8xxx_readb(chip->dev, SSBI_REG_ADDR_IRQ_ROOT, rp);
+}
+
+static int pm8xxx_read_master_irq(const struct pm_irq_chip *chip, u8 m, u8 *bp)
+{
+	return pm8xxx_readb(chip->dev,
+			SSBI_REG_ADDR_IRQ_M_STATUS1 + m, bp);
+}
+
+static int pm8xxx_read_block_irq(struct pm_irq_chip *chip, u8 bp, u8 *ip)
+{
+	int	rc;
+
+	spin_lock(&chip->pm_irq_lock);
+	rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_BLK_SEL, bp);
+	if (rc) {
+		pr_err("Failed Selecting Block %d rc=%d\n", bp, rc);
+		goto bail;
+	}
+
+	rc = pm8xxx_readb(chip->dev, SSBI_REG_ADDR_IRQ_IT_STATUS, ip);
+	if (rc)
+		pr_err("Failed Reading Status rc=%d\n", rc);
+bail:
+	spin_unlock(&chip->pm_irq_lock);
+	return rc;
+}
+
+static int pm8xxx_config_irq(struct pm_irq_chip *chip, u8 bp, u8 cp)
+{
+	int	rc;
+
+	spin_lock(&chip->pm_irq_lock);
+	rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_BLK_SEL, bp);
+	if (rc) {
+		pr_err("Failed Selecting Block %d rc=%d\n", bp, rc);
+		goto bail;
+	}
+
+	cp |= PM_IRQF_WRITE;
+	rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_CONFIG, cp);
+	if (rc)
+		pr_err("Failed Configuring IRQ rc=%d\n", rc);
+bail:
+	spin_unlock(&chip->pm_irq_lock);
+	return rc;
+}
+
+static int pm8xxx_irq_block_handler(struct pm_irq_chip *chip, int block)
+{
+	int pmirq, irq, i, ret = 0;
+	u8 bits;
+
+	ret = pm8xxx_read_block_irq(chip, block, &bits);
+	if (ret) {
+		pr_err("Failed reading %d block ret=%d", block, ret);
+		return ret;
+	}
+	if (!bits) {
+		pr_err("block bit set in master but no irqs: %d", block);
+		return 0;
+	}
+
+	/* Check IRQ bits */
+	for (i = 0; i < 8; i++) {
+		if (bits & (1 << i)) {
+			pmirq = block * 8 + i;
+			irq = pmirq + chip->irq_base;
+			generic_handle_irq(irq);
+		}
+	}
+	return 0;
+}
+
+static int pm8xxx_irq_master_handler(struct pm_irq_chip *chip, int master)
+{
+	u8 blockbits;
+	int block_number, i, ret = 0;
+
+	ret = pm8xxx_read_master_irq(chip, master, &blockbits);
+	if (ret) {
+		pr_err("Failed to read master %d ret=%d\n", master, ret);
+		return ret;
+	}
+	if (!blockbits) {
+		pr_err("master bit set in root but no blocks: %d", master);
+		return 0;
+	}
+
+	for (i = 0; i < 8; i++)
+		if (blockbits & (1 << i)) {
+			block_number = master * 8 + i;	/* block # */
+			ret |= pm8xxx_irq_block_handler(chip, block_number);
+		}
+	return ret;
+}
+
+static void pm8xxx_irq_handler(unsigned int irq, struct irq_desc *desc)
+{
+	struct pm_irq_chip *chip = irq_desc_get_handler_data(desc);
+	struct irq_chip *irq_chip = irq_desc_get_chip(desc);
+	u8	root;
+	int	i, ret, masters = 0;
+
+	ret = pm8xxx_read_root_irq(chip, &root);
+	if (ret) {
+		pr_err("Can't read root status ret=%d\n", ret);
+		return;
+	}
+
+	/* on pm8xxx series masters start from bit 1 of the root */
+	masters = root >> 1;
+
+	/* Read allowed masters for blocks. */
+	for (i = 0; i < chip->num_masters; i++)
+		if (masters & (1 << i))
+			pm8xxx_irq_master_handler(chip, i);
+
+	irq_chip->irq_ack(&desc->irq_data);
+}
+
+static void pm8xxx_irq_mask_ack(struct irq_data *d)
+{
+	struct pm_irq_chip *chip = irq_data_get_irq_chip_data(d);
+	unsigned int pmirq = d->irq - chip->irq_base;
+	int	master, irq_bit;
+	u8	block, config;
+
+	block = pmirq / 8;
+	master = block / 8;
+	irq_bit = pmirq % 8;
+
+	config = chip->config[pmirq] | PM_IRQF_MASK_ALL | PM_IRQF_CLR;
+	pm8xxx_config_irq(chip, block, config);
+}
+
+static void pm8xxx_irq_unmask(struct irq_data *d)
+{
+	struct pm_irq_chip *chip = irq_data_get_irq_chip_data(d);
+	unsigned int pmirq = d->irq - chip->irq_base;
+	int	master, irq_bit;
+	u8	block, config;
+
+	block = pmirq / 8;
+	master = block / 8;
+	irq_bit = pmirq % 8;
+
+	config = chip->config[pmirq];
+	pm8xxx_config_irq(chip, block, config);
+}
+
+static int pm8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
+{
+	struct pm_irq_chip *chip = irq_data_get_irq_chip_data(d);
+	unsigned int pmirq = d->irq - chip->irq_base;
+	int master, irq_bit;
+	u8 block, config;
+
+	block = pmirq / 8;
+	master = block / 8;
+	irq_bit  = pmirq % 8;
+
+	chip->config[pmirq] = (irq_bit << PM_IRQF_BITS_SHIFT)
+							| PM_IRQF_MASK_ALL;
+	if (flow_type & (IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING)) {
+		if (flow_type & IRQF_TRIGGER_RISING)
+			chip->config[pmirq] &= ~PM_IRQF_MASK_RE;
+		if (flow_type & IRQF_TRIGGER_FALLING)
+			chip->config[pmirq] &= ~PM_IRQF_MASK_FE;
+	} else {
+		chip->config[pmirq] |= PM_IRQF_LVL_SEL;
+
+		if (flow_type & IRQF_TRIGGER_HIGH)
+			chip->config[pmirq] &= ~PM_IRQF_MASK_RE;
+		else
+			chip->config[pmirq] &= ~PM_IRQF_MASK_FE;
+	}
+
+	config = chip->config[pmirq] | PM_IRQF_CLR;
+	return pm8xxx_config_irq(chip, block, config);
+}
+
+static int pm8xxx_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+	return 0;
+}
+
+static struct irq_chip pm8xxx_irq_chip = {
+	.name		= "pm8xxx",
+	.irq_mask_ack	= pm8xxx_irq_mask_ack,
+	.irq_unmask	= pm8xxx_irq_unmask,
+	.irq_set_type	= pm8xxx_irq_set_type,
+	.irq_set_wake	= pm8xxx_irq_set_wake,
+	.flags		= IRQCHIP_MASK_ON_SUSPEND,
+};
+
+/**
+ * pm8xxx_get_irq_stat - get the status of the irq line
+ * @chip: pointer to identify a pmic irq controller
+ * @irq: the irq number
+ *
+ * The pm8xxx gpio and mpp rely on the interrupt block to read
+ * the values on their pins. This function is to facilitate reading
+ * the status of a gpio or an mpp line. The caller has to convert the
+ * gpio number to irq number.
+ *
+ * RETURNS:
+ * an int indicating the value read on that line
+ */
+static int pm8xxx_get_irq_stat(struct pm_irq_chip *chip, int irq)
+{
+	int pmirq, rc;
+	u8  block, bits, bit;
+	unsigned long flags;
+
+	if (chip == NULL || irq < chip->irq_base ||
+			irq >= chip->irq_base + chip->num_irqs)
+		return -EINVAL;
+
+	pmirq = irq - chip->irq_base;
+
+	block = pmirq / 8;
+	bit = pmirq % 8;
+
+	spin_lock_irqsave(&chip->pm_irq_lock, flags);
+
+	rc = pm8xxx_writeb(chip->dev, SSBI_REG_ADDR_IRQ_BLK_SEL, block);
+	if (rc) {
+		pr_err("Failed Selecting block irq=%d pmirq=%d blk=%d rc=%d\n",
+			irq, pmirq, block, rc);
+		goto bail_out;
+	}
+
+	rc = pm8xxx_readb(chip->dev, SSBI_REG_ADDR_IRQ_RT_STATUS, &bits);
+	if (rc) {
+		pr_err("Failed Configuring irq=%d pmirq=%d blk=%d rc=%d\n",
+			irq, pmirq, block, rc);
+		goto bail_out;
+	}
+
+	rc = (bits & (1 << bit)) ? 1 : 0;
+
+bail_out:
+	spin_unlock_irqrestore(&chip->pm_irq_lock, flags);
+
+	return rc;
+}
+
+static struct pm_irq_chip *pm8xxx_irq_init(struct device *dev,
+				const struct pm8xxx_irq_platform_data *pdata)
+{
+	struct pm_irq_chip  *chip;
+	int devirq, rc;
+	unsigned int pmirq;
+
+	if (!pdata) {
+		pr_err("No platform data\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	devirq = pdata->devirq;
+	if (devirq < 0) {
+		pr_err("missing devirq\n");
+		rc = devirq;
+		return ERR_PTR(-EINVAL);
+	}
+
+	chip = kzalloc(sizeof(struct pm_irq_chip)
+			+ sizeof(u8) * pdata->irq_cdata.nirqs, GFP_KERNEL);
+	if (!chip) {
+		pr_err("Cannot alloc pm_irq_chip struct\n");
+		return ERR_PTR(-EINVAL);
+	}
+
+	chip->dev = dev;
+	chip->devirq = devirq;
+	chip->irq_base = pdata->irq_base;
+	chip->num_irqs = pdata->irq_cdata.nirqs;
+	chip->num_blocks = DIV_ROUND_UP(chip->num_irqs, 8);
+	chip->num_masters = DIV_ROUND_UP(chip->num_blocks, 8);
+	spin_lock_init(&chip->pm_irq_lock);
+
+	for (pmirq = 0; pmirq < chip->num_irqs; pmirq++) {
+		irq_set_chip_and_handler(chip->irq_base + pmirq,
+				&pm8xxx_irq_chip,
+				handle_level_irq);
+		irq_set_chip_data(chip->irq_base + pmirq, chip);
+#ifdef CONFIG_ARM
+		set_irq_flags(chip->irq_base + pmirq, IRQF_VALID);
+#else
+		irq_set_noprobe(chip->irq_base + pmirq);
+#endif
+	}
+
+	irq_set_irq_type(devirq, pdata->irq_trigger_flag);
+	irq_set_handler_data(devirq, chip);
+	irq_set_chained_handler(devirq, pm8xxx_irq_handler);
+	set_irq_wake(devirq, 1);
+
+	return chip;
+}
+
+static int pm8xxx_irq_exit(struct pm_irq_chip *chip)
+{
+	irq_set_chained_handler(chip->devirq, NULL);
+	kfree(chip);
+	return 0;
+}
+
 static int pm8921_readb(const struct device *dev, u16 addr, u8 *val)
 {
 	const struct pm8xxx_drvdata *pm8921_drvdata = dev_get_drvdata(dev);