From ace9429bb58fd418f0c81d4c2835699bddf6bde6 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Thu, 11 Apr 2024 10:27:49 +0200 Subject: Adding upstream version 6.6.15. Signed-off-by: Daniel Baumann --- drivers/gpio/gpio-grgpio.c | 466 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 466 insertions(+) create mode 100644 drivers/gpio/gpio-grgpio.c (limited to 'drivers/gpio/gpio-grgpio.c') diff --git a/drivers/gpio/gpio-grgpio.c b/drivers/gpio/gpio-grgpio.c new file mode 100644 index 0000000000..0163c95f6d --- /dev/null +++ b/drivers/gpio/gpio-grgpio.c @@ -0,0 +1,466 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * 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. + * + * Contributors: Andreas Larsson + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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 gpio_chip gc; + 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 void grgpio_set_imask(struct grgpio_priv *priv, unsigned int offset, + int val) +{ + struct gpio_chip *gc = &priv->gc; + + if (val) + priv->imask |= BIT(offset); + else + priv->imask &= ~BIT(offset); + gc->write_reg(priv->regs + GRGPIO_IMASK, priv->imask); +} + +static int grgpio_to_irq(struct gpio_chip *gc, unsigned offset) +{ + struct grgpio_priv *priv = gpiochip_get_data(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; + } + + raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags); + + ipol = priv->gc.read_reg(priv->regs + GRGPIO_IPOL) & ~mask; + iedge = priv->gc.read_reg(priv->regs + GRGPIO_IEDGE) & ~mask; + + priv->gc.write_reg(priv->regs + GRGPIO_IPOL, ipol | pol); + priv->gc.write_reg(priv->regs + GRGPIO_IEDGE, iedge | edge); + + raw_spin_unlock_irqrestore(&priv->gc.bgpio_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; + unsigned long flags; + + raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags); + + grgpio_set_imask(priv, offset, 0); + + raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); +} + +static void grgpio_irq_unmask(struct irq_data *d) +{ + struct grgpio_priv *priv = irq_data_get_irq_chip_data(d); + int offset = d->hwirq; + unsigned long flags; + + raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags); + + grgpio_set_imask(priv, offset, 1); + + raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); +} + +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->gc.ngpio; + unsigned long flags; + int i; + int match = 0; + + raw_spin_lock_irqsave(&priv->gc.bgpio_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; + } + } + + raw_spin_unlock_irqrestore(&priv->gc.bgpio_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 + */ +static 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); + + raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags); + + /* Request underlying irq if not already requested */ + lirq->irq = irq; + uirq = &priv->uirqs[lirq->index]; + if (uirq->refcnt == 0) { + raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); + 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); + return ret; + } + raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags); + } + uirq->refcnt++; + + raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); + + /* Setup irq */ + irq_set_chip_data(irq, priv); + irq_set_chip_and_handler(irq, &grgpio_irq_chip, + handle_simple_irq); + irq_set_noprobe(irq); + + return ret; +} + +static 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->gc.ngpio; + int i; + + irq_set_chip_and_handler(irq, NULL, NULL); + irq_set_chip_data(irq, NULL); + + raw_spin_lock_irqsave(&priv->gc.bgpio_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) { + raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); + free_irq(uirq->uirq, priv); + return; + } + } + + raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); +} + +static const 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 grgpio_priv *priv; + int err; + u32 prop; + s32 *irqmap; + int size; + int i; + + priv = devm_kzalloc(&ofdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + regs = devm_platform_ioremap_resource(ofdev, 0); + if (IS_ERR(regs)) + return PTR_ERR(regs); + + gc = &priv->gc; + err = bgpio_init(gc, &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 = gc->read_reg(regs + GRGPIO_IMASK); + priv->dev = &ofdev->dev; + + gc->owner = THIS_MODULE; + gc->to_irq = grgpio_to_irq; + gc->label = devm_kasprintf(&ofdev->dev, GFP_KERNEL, "%pOF", np); + 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 + */ + continue; + } + priv->uirqs[lirq->index].uirq = ret; + } + } + + platform_set_drvdata(ofdev, priv); + + err = gpiochip_add_data(gc, priv); + if (err) { + dev_err(&ofdev->dev, "Could not add gpiochip\n"); + if (priv->domain) + irq_domain_remove(priv->domain); + 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); + + gpiochip_remove(&priv->gc); + + if (priv->domain) + irq_domain_remove(priv->domain); + + return 0; +} + +static const 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", + .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"); -- cgit v1.2.3