diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-06 22:40:55 (GMT) |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-06 22:40:55 (GMT) |
commit | 30c67e93c526639aaac90fa873800104b7c16d16 (patch) | |
tree | 6d8d0fd248d4e60bdc175dacbd196fc44f23ce11 /drivers/gpio/gpio-grgpio.c | |
parent | f87bb9ee62700fa11713c630ac5671f253233b94 (diff) | |
parent | 08ffb2229fafc2c3a696b325a74bf4198d6b91d7 (diff) | |
download | linux-fsl-qoriq-30c67e93c526639aaac90fa873800104b7c16d16.tar.xz |
Merge tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux
Pull GPIO changes from Grant Likely:
"The usual selection of bug fixes and driver updates for GPIO. Nothing
really stands out except the addition of the GRGPIO driver and some
enhacements to ACPI support"
I'm pulling this despite the earlier mess. Let's hope it compiles these
days.
* tag 'gpio-for-linus' of git://git.secretlab.ca/git/linux: (46 commits)
gpio: grgpio: Add irq support
gpio: grgpio: Add device driver for GRGPIO cores
gpiolib-acpi: introduce acpi_get_gpio_by_index() helper
GPIO: gpio-generic: remove kfree() from bgpio_remove call
gpio / ACPI: Handle ACPI events in accordance with the spec
gpio: lpc32xx: Fix off-by-one valid range checking for bank
gpio: mcp23s08: convert driver to DT
gpio/omap: force restore if context loss is not detectable
gpio/omap: optimise interrupt service routine
gpio/omap: remove extra context restores in *_runtime_resume()
gpio/omap: free irq domain in probe() failure paths
gpio: gpio-generic: Add 16 and 32 bit big endian byte order support
gpio: samsung: Add terminating entry for exynos_pinctrl_ids
gpio: mvebu: add dbg_show function
MAX7301 GPIO: Do not force SPI speed when using OF Platform
gpio: gpio-tps65910.c: fix checkpatch error
gpio: gpio-timberdale.c: fix checkpatch error
gpio: gpio-tc3589x.c: fix checkpatch errors
gpio: gpio-stp-xway.c: fix checkpatch error
gpio: gpio-sch.c: fix checkpatch error
...
Diffstat (limited to 'drivers/gpio/gpio-grgpio.c')
-rw-r--r-- | drivers/gpio/gpio-grgpio.c | 505 |
1 files changed, 505 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-grgpio.c b/drivers/gpio/gpio-grgpio.c new file mode 100644 index 0000000..8e08b86 --- /dev/null +++ b/drivers/gpio/gpio-grgpio.c @@ -0,0 +1,505 @@ +/* + * Driver for Aeroflex Gaisler GRGPIO General Purpose I/O cores. + * + * 2013 (c) Aeroflex Gaisler AB + * + * This driver supports the GRGPIO GPIO core available in the GRLIB VHDL + * IP core library. + * + * Full documentation of the GRGPIO core can be found here: + * http://www.gaisler.com/products/grlib/grip.pdf + * + * See "Documentation/devicetree/bindings/gpio/gpio-grgpio.txt" for + * information on open firmware properties. + * + * 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. + * + * Contributors: Andreas Larsson <andreas@gaisler.com> + */ + +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/spinlock.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/of_gpio.h> +#include <linux/of_platform.h> +#include <linux/gpio.h> +#include <linux/slab.h> +#include <linux/err.h> +#include <linux/basic_mmio_gpio.h> +#include <linux/interrupt.h> +#include <linux/irq.h> +#include <linux/irqdomain.h> + +#define GRGPIO_MAX_NGPIO 32 + +#define GRGPIO_DATA 0x00 +#define GRGPIO_OUTPUT 0x04 +#define GRGPIO_DIR 0x08 +#define GRGPIO_IMASK 0x0c +#define GRGPIO_IPOL 0x10 +#define GRGPIO_IEDGE 0x14 +#define GRGPIO_BYPASS 0x18 +#define GRGPIO_IMAP_BASE 0x20 + +/* Structure for an irq of the core - called an underlying irq */ +struct grgpio_uirq { + u8 refcnt; /* Reference counter to manage requesting/freeing of uirq */ + u8 uirq; /* Underlying irq of the gpio driver */ +}; + +/* + * Structure for an irq of a gpio line handed out by this driver. The index is + * used to map to the corresponding underlying irq. + */ +struct grgpio_lirq { + s8 index; /* Index into struct grgpio_priv's uirqs, or -1 */ + u8 irq; /* irq for the gpio line */ +}; + +struct grgpio_priv { + struct bgpio_chip bgc; + void __iomem *regs; + struct device *dev; + + u32 imask; /* irq mask shadow register */ + + /* + * The grgpio core can have multiple "underlying" irqs. The gpio lines + * can be mapped to any one or none of these underlying irqs + * independently of each other. This driver sets up an irq domain and + * hands out separate irqs to each gpio line + */ + struct irq_domain *domain; + + /* + * This array contains information on each underlying irq, each + * irq of the grgpio core itself. + */ + struct grgpio_uirq uirqs[GRGPIO_MAX_NGPIO]; + + /* + * This array contains information for each gpio line on the irqs + * obtains from this driver. An index value of -1 for a certain gpio + * line indicates that the line has no irq. Otherwise the index connects + * the irq to the underlying irq by pointing into the uirqs array. + */ + struct grgpio_lirq lirqs[GRGPIO_MAX_NGPIO]; +}; + +static inline struct grgpio_priv *grgpio_gc_to_priv(struct gpio_chip *gc) +{ + struct bgpio_chip *bgc = to_bgpio_chip(gc); + + return container_of(bgc, struct grgpio_priv, bgc); +} + +static void grgpio_set_imask(struct grgpio_priv *priv, unsigned int offset, + int val) +{ + struct bgpio_chip *bgc = &priv->bgc; + unsigned long mask = bgc->pin2mask(bgc, offset); + unsigned long flags; + + spin_lock_irqsave(&bgc->lock, flags); + + if (val) + priv->imask |= mask; + else + priv->imask &= ~mask; + bgc->write_reg(priv->regs + GRGPIO_IMASK, priv->imask); + + spin_unlock_irqrestore(&bgc->lock, flags); +} + +static int grgpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct grgpio_priv *priv = grgpio_gc_to_priv(gc); + + if (offset > gc->ngpio) + return -ENXIO; + + if (priv->lirqs[offset].index < 0) + return -ENXIO; + + return irq_create_mapping(priv->domain, offset); +} + +/* -------------------- IRQ chip functions -------------------- */ + +static int grgpio_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct grgpio_priv *priv = irq_data_get_irq_chip_data(d); + unsigned long flags; + u32 mask = BIT(d->hwirq); + u32 ipol; + u32 iedge; + u32 pol; + u32 edge; + + switch (type) { + case IRQ_TYPE_LEVEL_LOW: + pol = 0; + edge = 0; + break; + case IRQ_TYPE_LEVEL_HIGH: + pol = mask; + edge = 0; + break; + case IRQ_TYPE_EDGE_FALLING: + pol = 0; + edge = mask; + break; + case IRQ_TYPE_EDGE_RISING: + pol = mask; + edge = mask; + break; + default: + return -EINVAL; + } + + spin_lock_irqsave(&priv->bgc.lock, flags); + + ipol = priv->bgc.read_reg(priv->regs + GRGPIO_IPOL) & ~mask; + iedge = priv->bgc.read_reg(priv->regs + GRGPIO_IEDGE) & ~mask; + + priv->bgc.write_reg(priv->regs + GRGPIO_IPOL, ipol | pol); + priv->bgc.write_reg(priv->regs + GRGPIO_IEDGE, iedge | edge); + + spin_unlock_irqrestore(&priv->bgc.lock, flags); + + return 0; +} + +static void grgpio_irq_mask(struct irq_data *d) +{ + struct grgpio_priv *priv = irq_data_get_irq_chip_data(d); + int offset = d->hwirq; + + grgpio_set_imask(priv, offset, 0); +} + +static void grgpio_irq_unmask(struct irq_data *d) +{ + struct grgpio_priv *priv = irq_data_get_irq_chip_data(d); + int offset = d->hwirq; + + grgpio_set_imask(priv, offset, 1); +} + +static struct irq_chip grgpio_irq_chip = { + .name = "grgpio", + .irq_mask = grgpio_irq_mask, + .irq_unmask = grgpio_irq_unmask, + .irq_set_type = grgpio_irq_set_type, +}; + +static irqreturn_t grgpio_irq_handler(int irq, void *dev) +{ + struct grgpio_priv *priv = dev; + int ngpio = priv->bgc.gc.ngpio; + unsigned long flags; + int i; + int match = 0; + + spin_lock_irqsave(&priv->bgc.lock, flags); + + /* + * For each gpio line, call its interrupt handler if it its underlying + * irq matches the current irq that is handled. + */ + for (i = 0; i < ngpio; i++) { + struct grgpio_lirq *lirq = &priv->lirqs[i]; + + if (priv->imask & BIT(i) && lirq->index >= 0 && + priv->uirqs[lirq->index].uirq == irq) { + generic_handle_irq(lirq->irq); + match = 1; + } + } + + spin_unlock_irqrestore(&priv->bgc.lock, flags); + + if (!match) + dev_warn(priv->dev, "No gpio line matched irq %d\n", irq); + + return IRQ_HANDLED; +} + +/* + * This function will be called as a consequence of the call to + * irq_create_mapping in grgpio_to_irq + */ +int grgpio_irq_map(struct irq_domain *d, unsigned int irq, + irq_hw_number_t hwirq) +{ + struct grgpio_priv *priv = d->host_data; + struct grgpio_lirq *lirq; + struct grgpio_uirq *uirq; + unsigned long flags; + int offset = hwirq; + int ret = 0; + + if (!priv) + return -EINVAL; + + lirq = &priv->lirqs[offset]; + if (lirq->index < 0) + return -EINVAL; + + dev_dbg(priv->dev, "Mapping irq %d for gpio line %d\n", + irq, offset); + + spin_lock_irqsave(&priv->bgc.lock, flags); + + /* Request underlying irq if not already requested */ + lirq->irq = irq; + uirq = &priv->uirqs[lirq->index]; + if (uirq->refcnt == 0) { + ret = request_irq(uirq->uirq, grgpio_irq_handler, 0, + dev_name(priv->dev), priv); + if (ret) { + dev_err(priv->dev, + "Could not request underlying irq %d\n", + uirq->uirq); + + spin_unlock_irqrestore(&priv->bgc.lock, flags); + + return ret; + } + } + uirq->refcnt++; + + spin_unlock_irqrestore(&priv->bgc.lock, flags); + + /* Setup irq */ + irq_set_chip_data(irq, priv); + irq_set_chip_and_handler(irq, &grgpio_irq_chip, + handle_simple_irq); + irq_clear_status_flags(irq, IRQ_NOREQUEST); +#ifdef CONFIG_ARM + set_irq_flags(irq, IRQF_VALID); +#else + irq_set_noprobe(irq); +#endif + + return ret; +} + +void grgpio_irq_unmap(struct irq_domain *d, unsigned int irq) +{ + struct grgpio_priv *priv = d->host_data; + int index; + struct grgpio_lirq *lirq; + struct grgpio_uirq *uirq; + unsigned long flags; + int ngpio = priv->bgc.gc.ngpio; + int i; + +#ifdef CONFIG_ARM + set_irq_flags(irq, 0); +#endif + irq_set_chip_and_handler(irq, NULL, NULL); + irq_set_chip_data(irq, NULL); + + spin_lock_irqsave(&priv->bgc.lock, flags); + + /* Free underlying irq if last user unmapped */ + index = -1; + for (i = 0; i < ngpio; i++) { + lirq = &priv->lirqs[i]; + if (lirq->irq == irq) { + grgpio_set_imask(priv, i, 0); + lirq->irq = 0; + index = lirq->index; + break; + } + } + WARN_ON(index < 0); + + if (index >= 0) { + uirq = &priv->uirqs[lirq->index]; + uirq->refcnt--; + if (uirq->refcnt == 0) + free_irq(uirq->uirq, priv); + } + + spin_unlock_irqrestore(&priv->bgc.lock, flags); +} + +static struct irq_domain_ops grgpio_irq_domain_ops = { + .map = grgpio_irq_map, + .unmap = grgpio_irq_unmap, +}; + +/* ------------------------------------------------------------ */ + +static int grgpio_probe(struct platform_device *ofdev) +{ + struct device_node *np = ofdev->dev.of_node; + void __iomem *regs; + struct gpio_chip *gc; + struct bgpio_chip *bgc; + struct grgpio_priv *priv; + struct resource *res; + int err; + u32 prop; + s32 *irqmap; + int size; + int i; + + priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + res = platform_get_resource(ofdev, IORESOURCE_MEM, 0); + regs = devm_ioremap_resource(&ofdev->dev, res); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + bgc = &priv->bgc; + err = bgpio_init(bgc, &ofdev->dev, 4, regs + GRGPIO_DATA, + regs + GRGPIO_OUTPUT, NULL, regs + GRGPIO_DIR, NULL, + BGPIOF_BIG_ENDIAN_BYTE_ORDER); + if (err) { + dev_err(&ofdev->dev, "bgpio_init() failed\n"); + return err; + } + + priv->regs = regs; + priv->imask = bgc->read_reg(regs + GRGPIO_IMASK); + priv->dev = &ofdev->dev; + + gc = &bgc->gc; + gc->of_node = np; + gc->owner = THIS_MODULE; + gc->to_irq = grgpio_to_irq; + gc->label = np->full_name; + gc->base = -1; + + err = of_property_read_u32(np, "nbits", &prop); + if (err || prop <= 0 || prop > GRGPIO_MAX_NGPIO) { + gc->ngpio = GRGPIO_MAX_NGPIO; + dev_dbg(&ofdev->dev, + "No or invalid nbits property: assume %d\n", gc->ngpio); + } else { + gc->ngpio = prop; + } + + /* + * The irqmap contains the index values indicating which underlying irq, + * if anyone, is connected to that line + */ + irqmap = (s32 *)of_get_property(np, "irqmap", &size); + if (irqmap) { + if (size < gc->ngpio) { + dev_err(&ofdev->dev, + "irqmap shorter than ngpio (%d < %d)\n", + size, gc->ngpio); + return -EINVAL; + } + + priv->domain = irq_domain_add_linear(np, gc->ngpio, + &grgpio_irq_domain_ops, + priv); + if (!priv->domain) { + dev_err(&ofdev->dev, "Could not add irq domain\n"); + return -EINVAL; + } + + for (i = 0; i < gc->ngpio; i++) { + struct grgpio_lirq *lirq; + int ret; + + lirq = &priv->lirqs[i]; + lirq->index = irqmap[i]; + + if (lirq->index < 0) + continue; + + ret = platform_get_irq(ofdev, lirq->index); + if (ret <= 0) { + /* + * Continue without irq functionality for that + * gpio line + */ + dev_err(priv->dev, + "Failed to get irq for offset %d\n", i); + continue; + } + priv->uirqs[lirq->index].uirq = ret; + } + } + + platform_set_drvdata(ofdev, priv); + + err = gpiochip_add(gc); + if (err) { + dev_err(&ofdev->dev, "Could not add gpiochip\n"); + return err; + } + + dev_info(&ofdev->dev, "regs=0x%p, base=%d, ngpio=%d, irqs=%s\n", + priv->regs, gc->base, gc->ngpio, priv->domain ? "on" : "off"); + + return 0; +} + +static int grgpio_remove(struct platform_device *ofdev) +{ + struct grgpio_priv *priv = platform_get_drvdata(ofdev); + unsigned long flags; + int i; + int ret = 0; + + spin_lock_irqsave(&priv->bgc.lock, flags); + + if (priv->domain) { + for (i = 0; i < GRGPIO_MAX_NGPIO; i++) { + if (priv->uirqs[i].refcnt != 0) { + ret = -EBUSY; + goto out; + } + } + } + + ret = gpiochip_remove(&priv->bgc.gc); + if (ret) + goto out; + + if (priv->domain) + irq_domain_remove(priv->domain); + +out: + spin_unlock_irqrestore(&priv->bgc.lock, flags); + + return ret; +} + +static struct of_device_id grgpio_match[] = { + {.name = "GAISLER_GPIO"}, + {.name = "01_01a"}, + {}, +}; + +MODULE_DEVICE_TABLE(of, grgpio_match); + +static struct platform_driver grgpio_driver = { + .driver = { + .name = "grgpio", + .owner = THIS_MODULE, + .of_match_table = grgpio_match, + }, + .probe = grgpio_probe, + .remove = grgpio_remove, +}; +module_platform_driver(grgpio_driver); + +MODULE_AUTHOR("Aeroflex Gaisler AB."); +MODULE_DESCRIPTION("Driver for Aeroflex Gaisler GRGPIO"); +MODULE_LICENSE("GPL"); |