| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 1 | From 8070fa91b95e20cd270c8d76bf45f2a5423358bf Mon Sep 17 00:00:00 2001 |
| 2 | From: Song Hui <hui.song_1@nxp.com> |
| 3 | Date: Fri, 6 Sep 2019 19:42:59 +0800 |
| 4 | Subject: [PATCH] gpio/mpc8xxx: change irq handler from chained to normal |
| 5 | |
| 6 | More than one gpio controllers can share one interrupt, change the |
| 7 | driver to request shared irq. |
| 8 | |
| 9 | While this will work, it will mess up userspace accounting of the number |
| 10 | of interrupts per second in tools such as vmstat. The reason is that |
| 11 | for every GPIO interrupt, /proc/interrupts records the count against GIC |
| 12 | interrupt 68 or 69, as well as the GPIO itself. So, for every GPIO |
| 13 | interrupt, the total number of interrupts that the system has seen |
| 14 | increments by two. |
| 15 | |
| 16 | Signed-off-by: Laurentiu Tudor <Laurentiu.Tudor@nxp.com> |
| 17 | Signed-off-by: Alex Marginean <alexandru.marginean@nxp.com> |
| 18 | Signed-off-by: Song Hui <hui.song_1@nxp.com> |
| 19 | --- |
| 20 | drivers/gpio/gpio-mpc8xxx.c | 30 +++++++++++++++++++----------- |
| 21 | 1 file changed, 19 insertions(+), 11 deletions(-) |
| 22 | |
| 23 | --- a/drivers/gpio/gpio-mpc8xxx.c |
| 24 | +++ b/drivers/gpio/gpio-mpc8xxx.c |
| 25 | @@ -22,6 +22,7 @@ |
| 26 | #include <linux/irq.h> |
| 27 | #include <linux/gpio/driver.h> |
| 28 | #include <linux/bitops.h> |
| 29 | +#include <linux/interrupt.h> |
| 30 | |
| 31 | #define MPC8XXX_GPIO_PINS 32 |
| 32 | |
| 33 | @@ -127,20 +128,19 @@ static int mpc8xxx_gpio_to_irq(struct gp |
| 34 | return -ENXIO; |
| 35 | } |
| 36 | |
| 37 | -static void mpc8xxx_gpio_irq_cascade(struct irq_desc *desc) |
| 38 | +static irqreturn_t mpc8xxx_gpio_irq_cascade(int irq, void *data) |
| 39 | { |
| 40 | - struct mpc8xxx_gpio_chip *mpc8xxx_gc = irq_desc_get_handler_data(desc); |
| 41 | - struct irq_chip *chip = irq_desc_get_chip(desc); |
| 42 | + struct mpc8xxx_gpio_chip *mpc8xxx_gc = data; |
| 43 | struct gpio_chip *gc = &mpc8xxx_gc->gc; |
| 44 | - unsigned int mask; |
| 45 | + unsigned long mask; |
| 46 | + int i; |
| 47 | |
| 48 | mask = gc->read_reg(mpc8xxx_gc->regs + GPIO_IER) |
| 49 | & gc->read_reg(mpc8xxx_gc->regs + GPIO_IMR); |
| 50 | - if (mask) |
| 51 | - generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq, |
| 52 | - 32 - ffs(mask))); |
| 53 | - if (chip->irq_eoi) |
| 54 | - chip->irq_eoi(&desc->irq_data); |
| 55 | + for_each_set_bit(i, &mask, 32) |
| 56 | + generic_handle_irq(irq_linear_revmap(mpc8xxx_gc->irq, 31 - i)); |
| 57 | + |
| 58 | + return IRQ_HANDLED; |
| 59 | } |
| 60 | |
| 61 | static void mpc8xxx_irq_unmask(struct irq_data *d) |
| 62 | @@ -415,8 +415,16 @@ static int mpc8xxx_probe(struct platform |
| 63 | if (devtype->gpio_dir_in_init) |
| 64 | devtype->gpio_dir_in_init(gc); |
| 65 | |
| 66 | - irq_set_chained_handler_and_data(mpc8xxx_gc->irqn, |
| 67 | - mpc8xxx_gpio_irq_cascade, mpc8xxx_gc); |
| 68 | + ret = devm_request_irq(&pdev->dev, mpc8xxx_gc->irqn, |
| 69 | + mpc8xxx_gpio_irq_cascade, |
| 70 | + IRQF_NO_THREAD | IRQF_SHARED, "gpio-cascade", |
| 71 | + mpc8xxx_gc); |
| 72 | + if (ret) { |
| 73 | + dev_err(&pdev->dev, "%s: failed to devm_request_irq(%d), ret = %d\n", |
| 74 | + np->full_name, mpc8xxx_gc->irqn, ret); |
| 75 | + goto err; |
| 76 | + } |
| 77 | + |
| 78 | return 0; |
| 79 | err: |
| 80 | iounmap(mpc8xxx_gc->regs); |