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path: root/drivers/gpio/gpio-aspeed.c
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Diffstat (limited to 'drivers/gpio/gpio-aspeed.c')
-rw-r--r--drivers/gpio/gpio-aspeed.c1244
1 files changed, 1244 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-aspeed.c b/drivers/gpio/gpio-aspeed.c
new file mode 100644
index 000000000..e627e0e90
--- /dev/null
+++ b/drivers/gpio/gpio-aspeed.c
@@ -0,0 +1,1244 @@
+/*
+ * Copyright 2015 IBM Corp.
+ *
+ * Joel Stanley <joel@jms.id.au>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <asm/div64.h>
+#include <linux/clk.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio/aspeed.h>
+#include <linux/hashtable.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+/*
+ * These two headers aren't meant to be used by GPIO drivers. We need
+ * them in order to access gpio_chip_hwgpio() which we need to implement
+ * the aspeed specific API which allows the coprocessor to request
+ * access to some GPIOs and to arbitrate between coprocessor and ARM.
+ */
+#include <linux/gpio/consumer.h>
+#include "gpiolib.h"
+
+struct aspeed_bank_props {
+ unsigned int bank;
+ u32 input;
+ u32 output;
+};
+
+struct aspeed_gpio_config {
+ unsigned int nr_gpios;
+ const struct aspeed_bank_props *props;
+};
+
+/*
+ * @offset_timer: Maps an offset to an @timer_users index, or zero if disabled
+ * @timer_users: Tracks the number of users for each timer
+ *
+ * The @timer_users has four elements but the first element is unused. This is
+ * to simplify accounting and indexing, as a zero value in @offset_timer
+ * represents disabled debouncing for the GPIO. Any other value for an element
+ * of @offset_timer is used as an index into @timer_users. This behaviour of
+ * the zero value aligns with the behaviour of zero built from the timer
+ * configuration registers (i.e. debouncing is disabled).
+ */
+struct aspeed_gpio {
+ struct gpio_chip chip;
+ spinlock_t lock;
+ void __iomem *base;
+ int irq;
+ const struct aspeed_gpio_config *config;
+
+ u8 *offset_timer;
+ unsigned int timer_users[4];
+ struct clk *clk;
+
+ u32 *dcache;
+ u8 *cf_copro_bankmap;
+};
+
+struct aspeed_gpio_bank {
+ uint16_t val_regs; /* +0: Rd: read input value, Wr: set write latch
+ * +4: Rd/Wr: Direction (0=in, 1=out)
+ */
+ uint16_t rdata_reg; /* Rd: read write latch, Wr: <none> */
+ uint16_t irq_regs;
+ uint16_t debounce_regs;
+ uint16_t tolerance_regs;
+ uint16_t cmdsrc_regs;
+ const char names[4][3];
+};
+
+/*
+ * Note: The "value" register returns the input value sampled on the
+ * line even when the GPIO is configured as an output. Since
+ * that input goes through synchronizers, writing, then reading
+ * back may not return the written value right away.
+ *
+ * The "rdata" register returns the content of the write latch
+ * and thus can be used to read back what was last written
+ * reliably.
+ */
+
+static const int debounce_timers[4] = { 0x00, 0x50, 0x54, 0x58 };
+
+static const struct aspeed_gpio_copro_ops *copro_ops;
+static void *copro_data;
+
+static const struct aspeed_gpio_bank aspeed_gpio_banks[] = {
+ {
+ .val_regs = 0x0000,
+ .rdata_reg = 0x00c0,
+ .irq_regs = 0x0008,
+ .debounce_regs = 0x0040,
+ .tolerance_regs = 0x001c,
+ .cmdsrc_regs = 0x0060,
+ .names = { "A", "B", "C", "D" },
+ },
+ {
+ .val_regs = 0x0020,
+ .rdata_reg = 0x00c4,
+ .irq_regs = 0x0028,
+ .debounce_regs = 0x0048,
+ .tolerance_regs = 0x003c,
+ .cmdsrc_regs = 0x0068,
+ .names = { "E", "F", "G", "H" },
+ },
+ {
+ .val_regs = 0x0070,
+ .rdata_reg = 0x00c8,
+ .irq_regs = 0x0098,
+ .debounce_regs = 0x00b0,
+ .tolerance_regs = 0x00ac,
+ .cmdsrc_regs = 0x0090,
+ .names = { "I", "J", "K", "L" },
+ },
+ {
+ .val_regs = 0x0078,
+ .rdata_reg = 0x00cc,
+ .irq_regs = 0x00e8,
+ .debounce_regs = 0x0100,
+ .tolerance_regs = 0x00fc,
+ .cmdsrc_regs = 0x00e0,
+ .names = { "M", "N", "O", "P" },
+ },
+ {
+ .val_regs = 0x0080,
+ .rdata_reg = 0x00d0,
+ .irq_regs = 0x0118,
+ .debounce_regs = 0x0130,
+ .tolerance_regs = 0x012c,
+ .cmdsrc_regs = 0x0110,
+ .names = { "Q", "R", "S", "T" },
+ },
+ {
+ .val_regs = 0x0088,
+ .rdata_reg = 0x00d4,
+ .irq_regs = 0x0148,
+ .debounce_regs = 0x0160,
+ .tolerance_regs = 0x015c,
+ .cmdsrc_regs = 0x0140,
+ .names = { "U", "V", "W", "X" },
+ },
+ {
+ .val_regs = 0x01E0,
+ .rdata_reg = 0x00d8,
+ .irq_regs = 0x0178,
+ .debounce_regs = 0x0190,
+ .tolerance_regs = 0x018c,
+ .cmdsrc_regs = 0x0170,
+ .names = { "Y", "Z", "AA", "AB" },
+ },
+ {
+ .val_regs = 0x01e8,
+ .rdata_reg = 0x00dc,
+ .irq_regs = 0x01a8,
+ .debounce_regs = 0x01c0,
+ .tolerance_regs = 0x01bc,
+ .cmdsrc_regs = 0x01a0,
+ .names = { "AC", "", "", "" },
+ },
+};
+
+enum aspeed_gpio_reg {
+ reg_val,
+ reg_rdata,
+ reg_dir,
+ reg_irq_enable,
+ reg_irq_type0,
+ reg_irq_type1,
+ reg_irq_type2,
+ reg_irq_status,
+ reg_debounce_sel1,
+ reg_debounce_sel2,
+ reg_tolerance,
+ reg_cmdsrc0,
+ reg_cmdsrc1,
+};
+
+#define GPIO_VAL_VALUE 0x00
+#define GPIO_VAL_DIR 0x04
+
+#define GPIO_IRQ_ENABLE 0x00
+#define GPIO_IRQ_TYPE0 0x04
+#define GPIO_IRQ_TYPE1 0x08
+#define GPIO_IRQ_TYPE2 0x0c
+#define GPIO_IRQ_STATUS 0x10
+
+#define GPIO_DEBOUNCE_SEL1 0x00
+#define GPIO_DEBOUNCE_SEL2 0x04
+
+#define GPIO_CMDSRC_0 0x00
+#define GPIO_CMDSRC_1 0x04
+#define GPIO_CMDSRC_ARM 0
+#define GPIO_CMDSRC_LPC 1
+#define GPIO_CMDSRC_COLDFIRE 2
+#define GPIO_CMDSRC_RESERVED 3
+
+/* This will be resolved at compile time */
+static inline void __iomem *bank_reg(struct aspeed_gpio *gpio,
+ const struct aspeed_gpio_bank *bank,
+ const enum aspeed_gpio_reg reg)
+{
+ switch (reg) {
+ case reg_val:
+ return gpio->base + bank->val_regs + GPIO_VAL_VALUE;
+ case reg_rdata:
+ return gpio->base + bank->rdata_reg;
+ case reg_dir:
+ return gpio->base + bank->val_regs + GPIO_VAL_DIR;
+ case reg_irq_enable:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_ENABLE;
+ case reg_irq_type0:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE0;
+ case reg_irq_type1:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE1;
+ case reg_irq_type2:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_TYPE2;
+ case reg_irq_status:
+ return gpio->base + bank->irq_regs + GPIO_IRQ_STATUS;
+ case reg_debounce_sel1:
+ return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL1;
+ case reg_debounce_sel2:
+ return gpio->base + bank->debounce_regs + GPIO_DEBOUNCE_SEL2;
+ case reg_tolerance:
+ return gpio->base + bank->tolerance_regs;
+ case reg_cmdsrc0:
+ return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_0;
+ case reg_cmdsrc1:
+ return gpio->base + bank->cmdsrc_regs + GPIO_CMDSRC_1;
+ }
+ BUG();
+}
+
+#define GPIO_BANK(x) ((x) >> 5)
+#define GPIO_OFFSET(x) ((x) & 0x1f)
+#define GPIO_BIT(x) BIT(GPIO_OFFSET(x))
+
+#define _GPIO_SET_DEBOUNCE(t, o, i) ((!!((t) & BIT(i))) << GPIO_OFFSET(o))
+#define GPIO_SET_DEBOUNCE1(t, o) _GPIO_SET_DEBOUNCE(t, o, 1)
+#define GPIO_SET_DEBOUNCE2(t, o) _GPIO_SET_DEBOUNCE(t, o, 0)
+
+static const struct aspeed_gpio_bank *to_bank(unsigned int offset)
+{
+ unsigned int bank = GPIO_BANK(offset);
+
+ WARN_ON(bank >= ARRAY_SIZE(aspeed_gpio_banks));
+ return &aspeed_gpio_banks[bank];
+}
+
+static inline bool is_bank_props_sentinel(const struct aspeed_bank_props *props)
+{
+ return !(props->input || props->output);
+}
+
+static inline const struct aspeed_bank_props *find_bank_props(
+ struct aspeed_gpio *gpio, unsigned int offset)
+{
+ const struct aspeed_bank_props *props = gpio->config->props;
+
+ while (!is_bank_props_sentinel(props)) {
+ if (props->bank == GPIO_BANK(offset))
+ return props;
+ props++;
+ }
+
+ return NULL;
+}
+
+static inline bool have_gpio(struct aspeed_gpio *gpio, unsigned int offset)
+{
+ const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ unsigned int group = GPIO_OFFSET(offset) / 8;
+
+ return bank->names[group][0] != '\0' &&
+ (!props || ((props->input | props->output) & GPIO_BIT(offset)));
+}
+
+static inline bool have_input(struct aspeed_gpio *gpio, unsigned int offset)
+{
+ const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
+
+ return !props || (props->input & GPIO_BIT(offset));
+}
+
+#define have_irq(g, o) have_input((g), (o))
+#define have_debounce(g, o) have_input((g), (o))
+
+static inline bool have_output(struct aspeed_gpio *gpio, unsigned int offset)
+{
+ const struct aspeed_bank_props *props = find_bank_props(gpio, offset);
+
+ return !props || (props->output & GPIO_BIT(offset));
+}
+
+static void aspeed_gpio_change_cmd_source(struct aspeed_gpio *gpio,
+ const struct aspeed_gpio_bank *bank,
+ int bindex, int cmdsrc)
+{
+ void __iomem *c0 = bank_reg(gpio, bank, reg_cmdsrc0);
+ void __iomem *c1 = bank_reg(gpio, bank, reg_cmdsrc1);
+ u32 bit, reg;
+
+ /*
+ * Each register controls 4 banks, so take the bottom 2
+ * bits of the bank index, and use them to select the
+ * right control bit (0, 8, 16 or 24).
+ */
+ bit = BIT((bindex & 3) << 3);
+
+ /* Source 1 first to avoid illegal 11 combination */
+ reg = ioread32(c1);
+ if (cmdsrc & 2)
+ reg |= bit;
+ else
+ reg &= ~bit;
+ iowrite32(reg, c1);
+
+ /* Then Source 0 */
+ reg = ioread32(c0);
+ if (cmdsrc & 1)
+ reg |= bit;
+ else
+ reg &= ~bit;
+ iowrite32(reg, c0);
+}
+
+static bool aspeed_gpio_copro_request(struct aspeed_gpio *gpio,
+ unsigned int offset)
+{
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+ if (!copro_ops || !gpio->cf_copro_bankmap)
+ return false;
+ if (!gpio->cf_copro_bankmap[offset >> 3])
+ return false;
+ if (!copro_ops->request_access)
+ return false;
+
+ /* Pause the coprocessor */
+ copro_ops->request_access(copro_data);
+
+ /* Change command source back to ARM */
+ aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3, GPIO_CMDSRC_ARM);
+
+ /* Update cache */
+ gpio->dcache[GPIO_BANK(offset)] = ioread32(bank_reg(gpio, bank, reg_rdata));
+
+ return true;
+}
+
+static void aspeed_gpio_copro_release(struct aspeed_gpio *gpio,
+ unsigned int offset)
+{
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+ if (!copro_ops || !gpio->cf_copro_bankmap)
+ return;
+ if (!gpio->cf_copro_bankmap[offset >> 3])
+ return;
+ if (!copro_ops->release_access)
+ return;
+
+ /* Change command source back to ColdFire */
+ aspeed_gpio_change_cmd_source(gpio, bank, offset >> 3,
+ GPIO_CMDSRC_COLDFIRE);
+
+ /* Restart the coprocessor */
+ copro_ops->release_access(copro_data);
+}
+
+static int aspeed_gpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+
+ return !!(ioread32(bank_reg(gpio, bank, reg_val)) & GPIO_BIT(offset));
+}
+
+static void __aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
+ int val)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ void __iomem *addr;
+ u32 reg;
+
+ addr = bank_reg(gpio, bank, reg_val);
+ reg = gpio->dcache[GPIO_BANK(offset)];
+
+ if (val)
+ reg |= GPIO_BIT(offset);
+ else
+ reg &= ~GPIO_BIT(offset);
+ gpio->dcache[GPIO_BANK(offset)] = reg;
+
+ iowrite32(reg, addr);
+}
+
+static void aspeed_gpio_set(struct gpio_chip *gc, unsigned int offset,
+ int val)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+ unsigned long flags;
+ bool copro;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
+
+ __aspeed_gpio_set(gc, offset, val);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static int aspeed_gpio_dir_in(struct gpio_chip *gc, unsigned int offset)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ void __iomem *addr = bank_reg(gpio, bank, reg_dir);
+ unsigned long flags;
+ bool copro;
+ u32 reg;
+
+ if (!have_input(gpio, offset))
+ return -ENOTSUPP;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ reg = ioread32(addr);
+ reg &= ~GPIO_BIT(offset);
+
+ copro = aspeed_gpio_copro_request(gpio, offset);
+ iowrite32(reg, addr);
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return 0;
+}
+
+static int aspeed_gpio_dir_out(struct gpio_chip *gc,
+ unsigned int offset, int val)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ void __iomem *addr = bank_reg(gpio, bank, reg_dir);
+ unsigned long flags;
+ bool copro;
+ u32 reg;
+
+ if (!have_output(gpio, offset))
+ return -ENOTSUPP;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ reg = ioread32(addr);
+ reg |= GPIO_BIT(offset);
+
+ copro = aspeed_gpio_copro_request(gpio, offset);
+ __aspeed_gpio_set(gc, offset, val);
+ iowrite32(reg, addr);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return 0;
+}
+
+static int aspeed_gpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(gc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ unsigned long flags;
+ u32 val;
+
+ if (!have_input(gpio, offset))
+ return 0;
+
+ if (!have_output(gpio, offset))
+ return 1;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ val = ioread32(bank_reg(gpio, bank, reg_dir)) & GPIO_BIT(offset);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return !val;
+
+}
+
+static inline int irqd_to_aspeed_gpio_data(struct irq_data *d,
+ struct aspeed_gpio **gpio,
+ const struct aspeed_gpio_bank **bank,
+ u32 *bit, int *offset)
+{
+ struct aspeed_gpio *internal;
+
+ *offset = irqd_to_hwirq(d);
+
+ internal = irq_data_get_irq_chip_data(d);
+
+ /* This might be a bit of a questionable place to check */
+ if (!have_irq(internal, *offset))
+ return -ENOTSUPP;
+
+ *gpio = internal;
+ *bank = to_bank(*offset);
+ *bit = GPIO_BIT(*offset);
+
+ return 0;
+}
+
+static void aspeed_gpio_irq_ack(struct irq_data *d)
+{
+ const struct aspeed_gpio_bank *bank;
+ struct aspeed_gpio *gpio;
+ unsigned long flags;
+ void __iomem *status_addr;
+ int rc, offset;
+ bool copro;
+ u32 bit;
+
+ rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
+ if (rc)
+ return;
+
+ status_addr = bank_reg(gpio, bank, reg_irq_status);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
+
+ iowrite32(bit, status_addr);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void aspeed_gpio_irq_set_mask(struct irq_data *d, bool set)
+{
+ const struct aspeed_gpio_bank *bank;
+ struct aspeed_gpio *gpio;
+ unsigned long flags;
+ u32 reg, bit;
+ void __iomem *addr;
+ int rc, offset;
+ bool copro;
+
+ rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
+ if (rc)
+ return;
+
+ addr = bank_reg(gpio, bank, reg_irq_enable);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
+
+ reg = ioread32(addr);
+ if (set)
+ reg |= bit;
+ else
+ reg &= ~bit;
+ iowrite32(reg, addr);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void aspeed_gpio_irq_mask(struct irq_data *d)
+{
+ aspeed_gpio_irq_set_mask(d, false);
+}
+
+static void aspeed_gpio_irq_unmask(struct irq_data *d)
+{
+ aspeed_gpio_irq_set_mask(d, true);
+}
+
+static int aspeed_gpio_set_type(struct irq_data *d, unsigned int type)
+{
+ u32 type0 = 0;
+ u32 type1 = 0;
+ u32 type2 = 0;
+ u32 bit, reg;
+ const struct aspeed_gpio_bank *bank;
+ irq_flow_handler_t handler;
+ struct aspeed_gpio *gpio;
+ unsigned long flags;
+ void __iomem *addr;
+ int rc, offset;
+ bool copro;
+
+ rc = irqd_to_aspeed_gpio_data(d, &gpio, &bank, &bit, &offset);
+ if (rc)
+ return -EINVAL;
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_BOTH:
+ type2 |= bit;
+ /* fall through */
+ case IRQ_TYPE_EDGE_RISING:
+ type0 |= bit;
+ /* fall through */
+ case IRQ_TYPE_EDGE_FALLING:
+ handler = handle_edge_irq;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ type0 |= bit;
+ /* fall through */
+ case IRQ_TYPE_LEVEL_LOW:
+ type1 |= bit;
+ handler = handle_level_irq;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
+
+ addr = bank_reg(gpio, bank, reg_irq_type0);
+ reg = ioread32(addr);
+ reg = (reg & ~bit) | type0;
+ iowrite32(reg, addr);
+
+ addr = bank_reg(gpio, bank, reg_irq_type1);
+ reg = ioread32(addr);
+ reg = (reg & ~bit) | type1;
+ iowrite32(reg, addr);
+
+ addr = bank_reg(gpio, bank, reg_irq_type2);
+ reg = ioread32(addr);
+ reg = (reg & ~bit) | type2;
+ iowrite32(reg, addr);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ irq_set_handler_locked(d, handler);
+
+ return 0;
+}
+
+static void aspeed_gpio_irq_handler(struct irq_desc *desc)
+{
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct irq_chip *ic = irq_desc_get_chip(desc);
+ struct aspeed_gpio *data = gpiochip_get_data(gc);
+ unsigned int i, p, girq;
+ unsigned long reg;
+
+ chained_irq_enter(ic, desc);
+
+ for (i = 0; i < ARRAY_SIZE(aspeed_gpio_banks); i++) {
+ const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
+
+ reg = ioread32(bank_reg(data, bank, reg_irq_status));
+
+ for_each_set_bit(p, &reg, 32) {
+ girq = irq_find_mapping(gc->irq.domain, i * 32 + p);
+ generic_handle_irq(girq);
+ }
+
+ }
+
+ chained_irq_exit(ic, desc);
+}
+
+static struct irq_chip aspeed_gpio_irqchip = {
+ .name = "aspeed-gpio",
+ .irq_ack = aspeed_gpio_irq_ack,
+ .irq_mask = aspeed_gpio_irq_mask,
+ .irq_unmask = aspeed_gpio_irq_unmask,
+ .irq_set_type = aspeed_gpio_set_type,
+};
+
+static void set_irq_valid_mask(struct aspeed_gpio *gpio)
+{
+ const struct aspeed_bank_props *props = gpio->config->props;
+
+ while (!is_bank_props_sentinel(props)) {
+ unsigned int offset;
+ const unsigned long int input = props->input;
+
+ /* Pretty crummy approach, but similar to GPIO core */
+ for_each_clear_bit(offset, &input, 32) {
+ unsigned int i = props->bank * 32 + offset;
+
+ if (i >= gpio->config->nr_gpios)
+ break;
+
+ clear_bit(i, gpio->chip.irq.valid_mask);
+ }
+
+ props++;
+ }
+}
+
+static int aspeed_gpio_setup_irqs(struct aspeed_gpio *gpio,
+ struct platform_device *pdev)
+{
+ int rc;
+
+ rc = platform_get_irq(pdev, 0);
+ if (rc < 0)
+ return rc;
+
+ gpio->irq = rc;
+
+ set_irq_valid_mask(gpio);
+
+ rc = gpiochip_irqchip_add(&gpio->chip, &aspeed_gpio_irqchip,
+ 0, handle_bad_irq, IRQ_TYPE_NONE);
+ if (rc) {
+ dev_info(&pdev->dev, "Could not add irqchip\n");
+ return rc;
+ }
+
+ gpiochip_set_chained_irqchip(&gpio->chip, &aspeed_gpio_irqchip,
+ gpio->irq, aspeed_gpio_irq_handler);
+
+ return 0;
+}
+
+static int aspeed_gpio_reset_tolerance(struct gpio_chip *chip,
+ unsigned int offset, bool enable)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ unsigned long flags;
+ void __iomem *treg;
+ bool copro;
+ u32 val;
+
+ treg = bank_reg(gpio, to_bank(offset), reg_tolerance);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+ copro = aspeed_gpio_copro_request(gpio, offset);
+
+ val = readl(treg);
+
+ if (enable)
+ val |= GPIO_BIT(offset);
+ else
+ val &= ~GPIO_BIT(offset);
+
+ writel(val, treg);
+
+ if (copro)
+ aspeed_gpio_copro_release(gpio, offset);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return 0;
+}
+
+static int aspeed_gpio_request(struct gpio_chip *chip, unsigned int offset)
+{
+ if (!have_gpio(gpiochip_get_data(chip), offset))
+ return -ENODEV;
+
+ return pinctrl_gpio_request(chip->base + offset);
+}
+
+static void aspeed_gpio_free(struct gpio_chip *chip, unsigned int offset)
+{
+ pinctrl_gpio_free(chip->base + offset);
+}
+
+static int usecs_to_cycles(struct aspeed_gpio *gpio, unsigned long usecs,
+ u32 *cycles)
+{
+ u64 rate;
+ u64 n;
+ u32 r;
+
+ rate = clk_get_rate(gpio->clk);
+ if (!rate)
+ return -ENOTSUPP;
+
+ n = rate * usecs;
+ r = do_div(n, 1000000);
+
+ if (n >= U32_MAX)
+ return -ERANGE;
+
+ /* At least as long as the requested time */
+ *cycles = n + (!!r);
+
+ return 0;
+}
+
+/* Call under gpio->lock */
+static int register_allocated_timer(struct aspeed_gpio *gpio,
+ unsigned int offset, unsigned int timer)
+{
+ if (WARN(gpio->offset_timer[offset] != 0,
+ "Offset %d already allocated timer %d\n",
+ offset, gpio->offset_timer[offset]))
+ return -EINVAL;
+
+ if (WARN(gpio->timer_users[timer] == UINT_MAX,
+ "Timer user count would overflow\n"))
+ return -EPERM;
+
+ gpio->offset_timer[offset] = timer;
+ gpio->timer_users[timer]++;
+
+ return 0;
+}
+
+/* Call under gpio->lock */
+static int unregister_allocated_timer(struct aspeed_gpio *gpio,
+ unsigned int offset)
+{
+ if (WARN(gpio->offset_timer[offset] == 0,
+ "No timer allocated to offset %d\n", offset))
+ return -EINVAL;
+
+ if (WARN(gpio->timer_users[gpio->offset_timer[offset]] == 0,
+ "No users recorded for timer %d\n",
+ gpio->offset_timer[offset]))
+ return -EINVAL;
+
+ gpio->timer_users[gpio->offset_timer[offset]]--;
+ gpio->offset_timer[offset] = 0;
+
+ return 0;
+}
+
+/* Call under gpio->lock */
+static inline bool timer_allocation_registered(struct aspeed_gpio *gpio,
+ unsigned int offset)
+{
+ return gpio->offset_timer[offset] > 0;
+}
+
+/* Call under gpio->lock */
+static void configure_timer(struct aspeed_gpio *gpio, unsigned int offset,
+ unsigned int timer)
+{
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ const u32 mask = GPIO_BIT(offset);
+ void __iomem *addr;
+ u32 val;
+
+ /* Note: Debounce timer isn't under control of the command
+ * source registers, so no need to sync with the coprocessor
+ */
+ addr = bank_reg(gpio, bank, reg_debounce_sel1);
+ val = ioread32(addr);
+ iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE1(timer, offset), addr);
+
+ addr = bank_reg(gpio, bank, reg_debounce_sel2);
+ val = ioread32(addr);
+ iowrite32((val & ~mask) | GPIO_SET_DEBOUNCE2(timer, offset), addr);
+}
+
+static int enable_debounce(struct gpio_chip *chip, unsigned int offset,
+ unsigned long usecs)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ u32 requested_cycles;
+ unsigned long flags;
+ int rc;
+ int i;
+
+ if (!gpio->clk)
+ return -EINVAL;
+
+ rc = usecs_to_cycles(gpio, usecs, &requested_cycles);
+ if (rc < 0) {
+ dev_warn(chip->parent, "Failed to convert %luus to cycles at %luHz: %d\n",
+ usecs, clk_get_rate(gpio->clk), rc);
+ return rc;
+ }
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ if (timer_allocation_registered(gpio, offset)) {
+ rc = unregister_allocated_timer(gpio, offset);
+ if (rc < 0)
+ goto out;
+ }
+
+ /* Try to find a timer already configured for the debounce period */
+ for (i = 1; i < ARRAY_SIZE(debounce_timers); i++) {
+ u32 cycles;
+
+ cycles = ioread32(gpio->base + debounce_timers[i]);
+ if (requested_cycles == cycles)
+ break;
+ }
+
+ if (i == ARRAY_SIZE(debounce_timers)) {
+ int j;
+
+ /*
+ * As there are no timers configured for the requested debounce
+ * period, find an unused timer instead
+ */
+ for (j = 1; j < ARRAY_SIZE(gpio->timer_users); j++) {
+ if (gpio->timer_users[j] == 0)
+ break;
+ }
+
+ if (j == ARRAY_SIZE(gpio->timer_users)) {
+ dev_warn(chip->parent,
+ "Debounce timers exhausted, cannot debounce for period %luus\n",
+ usecs);
+
+ rc = -EPERM;
+
+ /*
+ * We already adjusted the accounting to remove @offset
+ * as a user of its previous timer, so also configure
+ * the hardware so @offset has timers disabled for
+ * consistency.
+ */
+ configure_timer(gpio, offset, 0);
+ goto out;
+ }
+
+ i = j;
+
+ iowrite32(requested_cycles, gpio->base + debounce_timers[i]);
+ }
+
+ if (WARN(i == 0, "Cannot register index of disabled timer\n")) {
+ rc = -EINVAL;
+ goto out;
+ }
+
+ register_allocated_timer(gpio, offset, i);
+ configure_timer(gpio, offset, i);
+
+out:
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return rc;
+}
+
+static int disable_debounce(struct gpio_chip *chip, unsigned int offset)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ unsigned long flags;
+ int rc;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ rc = unregister_allocated_timer(gpio, offset);
+ if (!rc)
+ configure_timer(gpio, offset, 0);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ return rc;
+}
+
+static int set_debounce(struct gpio_chip *chip, unsigned int offset,
+ unsigned long usecs)
+{
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+
+ if (!have_debounce(gpio, offset))
+ return -ENOTSUPP;
+
+ if (usecs)
+ return enable_debounce(chip, offset, usecs);
+
+ return disable_debounce(chip, offset);
+}
+
+static int aspeed_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
+ unsigned long config)
+{
+ unsigned long param = pinconf_to_config_param(config);
+ u32 arg = pinconf_to_config_argument(config);
+
+ if (param == PIN_CONFIG_INPUT_DEBOUNCE)
+ return set_debounce(chip, offset, arg);
+ else if (param == PIN_CONFIG_BIAS_DISABLE ||
+ param == PIN_CONFIG_BIAS_PULL_DOWN ||
+ param == PIN_CONFIG_DRIVE_STRENGTH)
+ return pinctrl_gpio_set_config(offset, config);
+ else if (param == PIN_CONFIG_DRIVE_OPEN_DRAIN ||
+ param == PIN_CONFIG_DRIVE_OPEN_SOURCE)
+ /* Return -ENOTSUPP to trigger emulation, as per datasheet */
+ return -ENOTSUPP;
+ else if (param == PIN_CONFIG_PERSIST_STATE)
+ return aspeed_gpio_reset_tolerance(chip, offset, arg);
+
+ return -ENOTSUPP;
+}
+
+/**
+ * aspeed_gpio_copro_set_ops - Sets the callbacks used for handhsaking with
+ * the coprocessor for shared GPIO banks
+ * @ops: The callbacks
+ * @data: Pointer passed back to the callbacks
+ */
+int aspeed_gpio_copro_set_ops(const struct aspeed_gpio_copro_ops *ops, void *data)
+{
+ copro_data = data;
+ copro_ops = ops;
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_set_ops);
+
+/**
+ * aspeed_gpio_copro_grab_gpio - Mark a GPIO used by the coprocessor. The entire
+ * bank gets marked and any access from the ARM will
+ * result in handshaking via callbacks.
+ * @desc: The GPIO to be marked
+ * @vreg_offset: If non-NULL, returns the value register offset in the GPIO space
+ * @dreg_offset: If non-NULL, returns the data latch register offset in the GPIO space
+ * @bit: If non-NULL, returns the bit number of the GPIO in the registers
+ */
+int aspeed_gpio_copro_grab_gpio(struct gpio_desc *desc,
+ u16 *vreg_offset, u16 *dreg_offset, u8 *bit)
+{
+ struct gpio_chip *chip = gpiod_to_chip(desc);
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ unsigned long flags;
+
+ if (!gpio->cf_copro_bankmap)
+ gpio->cf_copro_bankmap = kzalloc(gpio->config->nr_gpios >> 3, GFP_KERNEL);
+ if (!gpio->cf_copro_bankmap)
+ return -ENOMEM;
+ if (offset < 0 || offset > gpio->config->nr_gpios)
+ return -EINVAL;
+ bindex = offset >> 3;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ /* Sanity check, this shouldn't happen */
+ if (gpio->cf_copro_bankmap[bindex] == 0xff) {
+ rc = -EIO;
+ goto bail;
+ }
+ gpio->cf_copro_bankmap[bindex]++;
+
+ /* Switch command source */
+ if (gpio->cf_copro_bankmap[bindex] == 1)
+ aspeed_gpio_change_cmd_source(gpio, bank, bindex,
+ GPIO_CMDSRC_COLDFIRE);
+
+ if (vreg_offset)
+ *vreg_offset = bank->val_regs;
+ if (dreg_offset)
+ *dreg_offset = bank->rdata_reg;
+ if (bit)
+ *bit = GPIO_OFFSET(offset);
+ bail:
+ spin_unlock_irqrestore(&gpio->lock, flags);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_grab_gpio);
+
+/**
+ * aspeed_gpio_copro_release_gpio - Unmark a GPIO used by the coprocessor.
+ * @desc: The GPIO to be marked
+ */
+int aspeed_gpio_copro_release_gpio(struct gpio_desc *desc)
+{
+ struct gpio_chip *chip = gpiod_to_chip(desc);
+ struct aspeed_gpio *gpio = gpiochip_get_data(chip);
+ int rc = 0, bindex, offset = gpio_chip_hwgpio(desc);
+ const struct aspeed_gpio_bank *bank = to_bank(offset);
+ unsigned long flags;
+
+ if (!gpio->cf_copro_bankmap)
+ return -ENXIO;
+
+ if (offset < 0 || offset > gpio->config->nr_gpios)
+ return -EINVAL;
+ bindex = offset >> 3;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ /* Sanity check, this shouldn't happen */
+ if (gpio->cf_copro_bankmap[bindex] == 0) {
+ rc = -EIO;
+ goto bail;
+ }
+ gpio->cf_copro_bankmap[bindex]--;
+
+ /* Switch command source */
+ if (gpio->cf_copro_bankmap[bindex] == 0)
+ aspeed_gpio_change_cmd_source(gpio, bank, bindex,
+ GPIO_CMDSRC_ARM);
+ bail:
+ spin_unlock_irqrestore(&gpio->lock, flags);
+ return rc;
+}
+EXPORT_SYMBOL_GPL(aspeed_gpio_copro_release_gpio);
+
+/*
+ * Any banks not specified in a struct aspeed_bank_props array are assumed to
+ * have the properties:
+ *
+ * { .input = 0xffffffff, .output = 0xffffffff }
+ */
+
+static const struct aspeed_bank_props ast2400_bank_props[] = {
+ /* input output */
+ { 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
+ { 6, 0x0000000f, 0x0fffff0f }, /* Y/Z/AA/AB, two 4-GPIO holes */
+ { },
+};
+
+static const struct aspeed_gpio_config ast2400_config =
+ /* 220 for simplicity, really 216 with two 4-GPIO holes, four at end */
+ { .nr_gpios = 220, .props = ast2400_bank_props, };
+
+static const struct aspeed_bank_props ast2500_bank_props[] = {
+ /* input output */
+ { 5, 0xffffffff, 0x0000ffff }, /* U/V/W/X */
+ { 6, 0x0fffffff, 0x0fffffff }, /* Y/Z/AA/AB, 4-GPIO hole */
+ { 7, 0x000000ff, 0x000000ff }, /* AC */
+ { },
+};
+
+static const struct aspeed_gpio_config ast2500_config =
+ /* 232 for simplicity, actual number is 228 (4-GPIO hole in GPIOAB) */
+ { .nr_gpios = 232, .props = ast2500_bank_props, };
+
+static const struct of_device_id aspeed_gpio_of_table[] = {
+ { .compatible = "aspeed,ast2400-gpio", .data = &ast2400_config, },
+ { .compatible = "aspeed,ast2500-gpio", .data = &ast2500_config, },
+ {}
+};
+MODULE_DEVICE_TABLE(of, aspeed_gpio_of_table);
+
+static int __init aspeed_gpio_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *gpio_id;
+ struct aspeed_gpio *gpio;
+ struct resource *res;
+ int rc, i, banks;
+
+ gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
+ if (!gpio)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ gpio->base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(gpio->base))
+ return PTR_ERR(gpio->base);
+
+ spin_lock_init(&gpio->lock);
+
+ gpio_id = of_match_node(aspeed_gpio_of_table, pdev->dev.of_node);
+ if (!gpio_id)
+ return -EINVAL;
+
+ gpio->clk = of_clk_get(pdev->dev.of_node, 0);
+ if (IS_ERR(gpio->clk)) {
+ dev_warn(&pdev->dev,
+ "Failed to get clock from devicetree, debouncing disabled\n");
+ gpio->clk = NULL;
+ }
+
+ gpio->config = gpio_id->data;
+
+ gpio->chip.parent = &pdev->dev;
+ gpio->chip.ngpio = gpio->config->nr_gpios;
+ gpio->chip.parent = &pdev->dev;
+ gpio->chip.direction_input = aspeed_gpio_dir_in;
+ gpio->chip.direction_output = aspeed_gpio_dir_out;
+ gpio->chip.get_direction = aspeed_gpio_get_direction;
+ gpio->chip.request = aspeed_gpio_request;
+ gpio->chip.free = aspeed_gpio_free;
+ gpio->chip.get = aspeed_gpio_get;
+ gpio->chip.set = aspeed_gpio_set;
+ gpio->chip.set_config = aspeed_gpio_set_config;
+ gpio->chip.label = dev_name(&pdev->dev);
+ gpio->chip.base = -1;
+ gpio->chip.irq.need_valid_mask = true;
+
+ /* Allocate a cache of the output registers */
+ banks = DIV_ROUND_UP(gpio->config->nr_gpios, 32);
+ gpio->dcache = devm_kcalloc(&pdev->dev,
+ banks, sizeof(u32), GFP_KERNEL);
+ if (!gpio->dcache)
+ return -ENOMEM;
+
+ /*
+ * Populate it with initial values read from the HW and switch
+ * all command sources to the ARM by default
+ */
+ for (i = 0; i < banks; i++) {
+ const struct aspeed_gpio_bank *bank = &aspeed_gpio_banks[i];
+ void __iomem *addr = bank_reg(gpio, bank, reg_rdata);
+ gpio->dcache[i] = ioread32(addr);
+ aspeed_gpio_change_cmd_source(gpio, bank, 0, GPIO_CMDSRC_ARM);
+ aspeed_gpio_change_cmd_source(gpio, bank, 1, GPIO_CMDSRC_ARM);
+ aspeed_gpio_change_cmd_source(gpio, bank, 2, GPIO_CMDSRC_ARM);
+ aspeed_gpio_change_cmd_source(gpio, bank, 3, GPIO_CMDSRC_ARM);
+ }
+
+ rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
+ if (rc < 0)
+ return rc;
+
+ gpio->offset_timer =
+ devm_kzalloc(&pdev->dev, gpio->chip.ngpio, GFP_KERNEL);
+ if (!gpio->offset_timer)
+ return -ENOMEM;
+
+ return aspeed_gpio_setup_irqs(gpio, pdev);
+}
+
+static struct platform_driver aspeed_gpio_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = aspeed_gpio_of_table,
+ },
+};
+
+module_platform_driver_probe(aspeed_gpio_driver, aspeed_gpio_probe);
+
+MODULE_DESCRIPTION("Aspeed GPIO Driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-27 14:44:10 +0000