diff options
Diffstat (limited to 'drivers/platform/cznic/turris-omnia-mcu-gpio.c')
| -rw-r--r-- | drivers/platform/cznic/turris-omnia-mcu-gpio.c | 1095 |
1 files changed, 1095 insertions, 0 deletions
diff --git a/drivers/platform/cznic/turris-omnia-mcu-gpio.c b/drivers/platform/cznic/turris-omnia-mcu-gpio.c new file mode 100644 index 000000000000..7ffc9453eddb --- /dev/null +++ b/drivers/platform/cznic/turris-omnia-mcu-gpio.c @@ -0,0 +1,1095 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * CZ.NIC's Turris Omnia MCU GPIO and IRQ driver + * + * 2024 by Marek Behún <kabel@kernel.org> + */ + +#include <linux/array_size.h> +#include <linux/bitfield.h> +#include <linux/bitops.h> +#include <linux/bug.h> +#include <linux/cleanup.h> +#include <linux/device.h> +#include <linux/devm-helpers.h> +#include <linux/errno.h> +#include <linux/gpio/driver.h> +#include <linux/i2c.h> +#include <linux/interrupt.h> +#include <linux/mutex.h> +#include <linux/sysfs.h> +#include <linux/types.h> +#include <linux/workqueue.h> +#include <asm/unaligned.h> + +#include <linux/turris-omnia-mcu-interface.h> +#include "turris-omnia-mcu.h" + +#define OMNIA_CMD_INT_ARG_LEN 8 +#define FRONT_BUTTON_RELEASE_DELAY_MS 50 + +static const char * const omnia_mcu_gpio_templates[64] = { + /* GPIOs with value read from the 16-bit wide status */ + [4] = "MiniPCIe0 Card Detect", + [5] = "MiniPCIe0 mSATA Indicator", + [6] = "Front USB3 port over-current", + [7] = "Rear USB3 port over-current", + [8] = "Front USB3 port power", + [9] = "Rear USB3 port power", + [12] = "Front Button", + + /* GPIOs with value read from the 32-bit wide extended status */ + [16] = "SFP nDET", + [28] = "MiniPCIe0 LED", + [29] = "MiniPCIe1 LED", + [30] = "MiniPCIe2 LED", + [31] = "MiniPCIe0 PAN LED", + [32] = "MiniPCIe1 PAN LED", + [33] = "MiniPCIe2 PAN LED", + [34] = "WAN PHY LED0", + [35] = "WAN PHY LED1", + [36] = "LAN switch p0 LED0", + [37] = "LAN switch p0 LED1", + [38] = "LAN switch p1 LED0", + [39] = "LAN switch p1 LED1", + [40] = "LAN switch p2 LED0", + [41] = "LAN switch p2 LED1", + [42] = "LAN switch p3 LED0", + [43] = "LAN switch p3 LED1", + [44] = "LAN switch p4 LED0", + [45] = "LAN switch p4 LED1", + [46] = "LAN switch p5 LED0", + [47] = "LAN switch p5 LED1", + + /* GPIOs with value read from the 16-bit wide extended control status */ + [48] = "eMMC nRESET", + [49] = "LAN switch nRESET", + [50] = "WAN PHY nRESET", + [51] = "MiniPCIe0 nPERST", + [52] = "MiniPCIe1 nPERST", + [53] = "MiniPCIe2 nPERST", + [54] = "WAN PHY SFP mux", + [56] = "VHV power disable", +}; + +struct omnia_gpio { + u8 cmd; + u8 ctl_cmd; + u8 bit; + u8 ctl_bit; + u8 int_bit; + u16 feat; + u16 feat_mask; +}; + +#define OMNIA_GPIO_INVALID_INT_BIT 0xff + +#define _DEF_GPIO(_cmd, _ctl_cmd, _bit, _ctl_bit, _int_bit, _feat, _feat_mask) \ + { \ + .cmd = _cmd, \ + .ctl_cmd = _ctl_cmd, \ + .bit = _bit, \ + .ctl_bit = _ctl_bit, \ + .int_bit = (_int_bit) < 0 ? OMNIA_GPIO_INVALID_INT_BIT \ + : (_int_bit), \ + .feat = _feat, \ + .feat_mask = _feat_mask, \ + } + +#define _DEF_GPIO_STS(_name) \ + _DEF_GPIO(OMNIA_CMD_GET_STATUS_WORD, 0, __bf_shf(OMNIA_STS_ ## _name), \ + 0, __bf_shf(OMNIA_INT_ ## _name), 0, 0) + +#define _DEF_GPIO_CTL(_name) \ + _DEF_GPIO(OMNIA_CMD_GET_STATUS_WORD, OMNIA_CMD_GENERAL_CONTROL, \ + __bf_shf(OMNIA_STS_ ## _name), __bf_shf(OMNIA_CTL_ ## _name), \ + -1, 0, 0) + +#define _DEF_GPIO_EXT_STS(_name, _feat) \ + _DEF_GPIO(OMNIA_CMD_GET_EXT_STATUS_DWORD, 0, \ + __bf_shf(OMNIA_EXT_STS_ ## _name), 0, \ + __bf_shf(OMNIA_INT_ ## _name), \ + OMNIA_FEAT_ ## _feat | OMNIA_FEAT_EXT_CMDS, \ + OMNIA_FEAT_ ## _feat | OMNIA_FEAT_EXT_CMDS) + +#define _DEF_GPIO_EXT_STS_LED(_name, _ledext) \ + _DEF_GPIO(OMNIA_CMD_GET_EXT_STATUS_DWORD, 0, \ + __bf_shf(OMNIA_EXT_STS_ ## _name), 0, \ + __bf_shf(OMNIA_INT_ ## _name), \ + OMNIA_FEAT_LED_STATE_ ## _ledext, \ + OMNIA_FEAT_LED_STATE_EXT_MASK) + +#define _DEF_GPIO_EXT_STS_LEDALL(_name) \ + _DEF_GPIO(OMNIA_CMD_GET_EXT_STATUS_DWORD, 0, \ + __bf_shf(OMNIA_EXT_STS_ ## _name), 0, \ + __bf_shf(OMNIA_INT_ ## _name), \ + OMNIA_FEAT_LED_STATE_EXT_MASK, 0) + +#define _DEF_GPIO_EXT_CTL(_name, _feat) \ + _DEF_GPIO(OMNIA_CMD_GET_EXT_CONTROL_STATUS, OMNIA_CMD_EXT_CONTROL, \ + __bf_shf(OMNIA_EXT_CTL_ ## _name), \ + __bf_shf(OMNIA_EXT_CTL_ ## _name), -1, \ + OMNIA_FEAT_ ## _feat | OMNIA_FEAT_EXT_CMDS, \ + OMNIA_FEAT_ ## _feat | OMNIA_FEAT_EXT_CMDS) + +#define _DEF_INT(_name) \ + _DEF_GPIO(0, 0, 0, 0, __bf_shf(OMNIA_INT_ ## _name), 0, 0) + +static inline bool is_int_bit_valid(const struct omnia_gpio *gpio) +{ + return gpio->int_bit != OMNIA_GPIO_INVALID_INT_BIT; +} + +static const struct omnia_gpio omnia_gpios[64] = { + /* GPIOs with value read from the 16-bit wide status */ + [4] = _DEF_GPIO_STS(CARD_DET), + [5] = _DEF_GPIO_STS(MSATA_IND), + [6] = _DEF_GPIO_STS(USB30_OVC), + [7] = _DEF_GPIO_STS(USB31_OVC), + [8] = _DEF_GPIO_CTL(USB30_PWRON), + [9] = _DEF_GPIO_CTL(USB31_PWRON), + + /* brightness changed interrupt, no GPIO */ + [11] = _DEF_INT(BRIGHTNESS_CHANGED), + + [12] = _DEF_GPIO_STS(BUTTON_PRESSED), + + /* TRNG interrupt, no GPIO */ + [13] = _DEF_INT(TRNG), + + /* MESSAGE_SIGNED interrupt, no GPIO */ + [14] = _DEF_INT(MESSAGE_SIGNED), + + /* GPIOs with value read from the 32-bit wide extended status */ + [16] = _DEF_GPIO_EXT_STS(SFP_nDET, PERIPH_MCU), + [28] = _DEF_GPIO_EXT_STS_LEDALL(WLAN0_MSATA_LED), + [29] = _DEF_GPIO_EXT_STS_LEDALL(WLAN1_LED), + [30] = _DEF_GPIO_EXT_STS_LEDALL(WLAN2_LED), + [31] = _DEF_GPIO_EXT_STS_LED(WPAN0_LED, EXT), + [32] = _DEF_GPIO_EXT_STS_LED(WPAN1_LED, EXT), + [33] = _DEF_GPIO_EXT_STS_LED(WPAN2_LED, EXT), + [34] = _DEF_GPIO_EXT_STS_LEDALL(WAN_LED0), + [35] = _DEF_GPIO_EXT_STS_LED(WAN_LED1, EXT_V32), + [36] = _DEF_GPIO_EXT_STS_LEDALL(LAN0_LED0), + [37] = _DEF_GPIO_EXT_STS_LEDALL(LAN0_LED1), + [38] = _DEF_GPIO_EXT_STS_LEDALL(LAN1_LED0), + [39] = _DEF_GPIO_EXT_STS_LEDALL(LAN1_LED1), + [40] = _DEF_GPIO_EXT_STS_LEDALL(LAN2_LED0), + [41] = _DEF_GPIO_EXT_STS_LEDALL(LAN2_LED1), + [42] = _DEF_GPIO_EXT_STS_LEDALL(LAN3_LED0), + [43] = _DEF_GPIO_EXT_STS_LEDALL(LAN3_LED1), + [44] = _DEF_GPIO_EXT_STS_LEDALL(LAN4_LED0), + [45] = _DEF_GPIO_EXT_STS_LEDALL(LAN4_LED1), + [46] = _DEF_GPIO_EXT_STS_LEDALL(LAN5_LED0), + [47] = _DEF_GPIO_EXT_STS_LEDALL(LAN5_LED1), + + /* GPIOs with value read from the 16-bit wide extended control status */ + [48] = _DEF_GPIO_EXT_CTL(nRES_MMC, PERIPH_MCU), + [49] = _DEF_GPIO_EXT_CTL(nRES_LAN, PERIPH_MCU), + [50] = _DEF_GPIO_EXT_CTL(nRES_PHY, PERIPH_MCU), + [51] = _DEF_GPIO_EXT_CTL(nPERST0, PERIPH_MCU), + [52] = _DEF_GPIO_EXT_CTL(nPERST1, PERIPH_MCU), + [53] = _DEF_GPIO_EXT_CTL(nPERST2, PERIPH_MCU), + [54] = _DEF_GPIO_EXT_CTL(PHY_SFP, PERIPH_MCU), + [56] = _DEF_GPIO_EXT_CTL(nVHV_CTRL, PERIPH_MCU), +}; + +/* mapping from interrupts to indexes of GPIOs in the omnia_gpios array */ +static const u8 omnia_int_to_gpio_idx[32] = { + [__bf_shf(OMNIA_INT_CARD_DET)] = 4, + [__bf_shf(OMNIA_INT_MSATA_IND)] = 5, + [__bf_shf(OMNIA_INT_USB30_OVC)] = 6, + [__bf_shf(OMNIA_INT_USB31_OVC)] = 7, + [__bf_shf(OMNIA_INT_BUTTON_PRESSED)] = 12, + [__bf_shf(OMNIA_INT_TRNG)] = 13, + [__bf_shf(OMNIA_INT_MESSAGE_SIGNED)] = 14, + [__bf_shf(OMNIA_INT_SFP_nDET)] = 16, + [__bf_shf(OMNIA_INT_BRIGHTNESS_CHANGED)] = 11, + [__bf_shf(OMNIA_INT_WLAN0_MSATA_LED)] = 28, + [__bf_shf(OMNIA_INT_WLAN1_LED)] = 29, + [__bf_shf(OMNIA_INT_WLAN2_LED)] = 30, + [__bf_shf(OMNIA_INT_WPAN0_LED)] = 31, + [__bf_shf(OMNIA_INT_WPAN1_LED)] = 32, + [__bf_shf(OMNIA_INT_WPAN2_LED)] = 33, + [__bf_shf(OMNIA_INT_WAN_LED0)] = 34, + [__bf_shf(OMNIA_INT_WAN_LED1)] = 35, + [__bf_shf(OMNIA_INT_LAN0_LED0)] = 36, + [__bf_shf(OMNIA_INT_LAN0_LED1)] = 37, + [__bf_shf(OMNIA_INT_LAN1_LED0)] = 38, + [__bf_shf(OMNIA_INT_LAN1_LED1)] = 39, + [__bf_shf(OMNIA_INT_LAN2_LED0)] = 40, + [__bf_shf(OMNIA_INT_LAN2_LED1)] = 41, + [__bf_shf(OMNIA_INT_LAN3_LED0)] = 42, + [__bf_shf(OMNIA_INT_LAN3_LED1)] = 43, + [__bf_shf(OMNIA_INT_LAN4_LED0)] = 44, + [__bf_shf(OMNIA_INT_LAN4_LED1)] = 45, + [__bf_shf(OMNIA_INT_LAN5_LED0)] = 46, + [__bf_shf(OMNIA_INT_LAN5_LED1)] = 47, +}; + +/* index of PHY_SFP GPIO in the omnia_gpios array */ +#define OMNIA_GPIO_PHY_SFP_OFFSET 54 + +static int omnia_ctl_cmd_locked(struct omnia_mcu *mcu, u8 cmd, u16 val, u16 mask) +{ + unsigned int len; + u8 buf[5]; + + buf[0] = cmd; + + switch (cmd) { + case OMNIA_CMD_GENERAL_CONTROL: + buf[1] = val; + buf[2] = mask; + len = 3; + break; + + case OMNIA_CMD_EXT_CONTROL: + put_unaligned_le16(val, &buf[1]); + put_unaligned_le16(mask, &buf[3]); + len = 5; + break; + + default: + BUG(); + } + + return omnia_cmd_write(mcu->client, buf, len); +} + +static int omnia_ctl_cmd(struct omnia_mcu *mcu, u8 cmd, u16 val, u16 mask) +{ + guard(mutex)(&mcu->lock); + + return omnia_ctl_cmd_locked(mcu, cmd, val, mask); +} + +static int omnia_gpio_request(struct gpio_chip *gc, unsigned int offset) +{ + if (!omnia_gpios[offset].cmd) + return -EINVAL; + + return 0; +} + +static int omnia_gpio_get_direction(struct gpio_chip *gc, unsigned int offset) +{ + struct omnia_mcu *mcu = gpiochip_get_data(gc); + + if (offset == OMNIA_GPIO_PHY_SFP_OFFSET) { + int val; + + scoped_guard(mutex, &mcu->lock) { + val = omnia_cmd_read_bit(mcu->client, + OMNIA_CMD_GET_EXT_CONTROL_STATUS, + OMNIA_EXT_CTL_PHY_SFP_AUTO); + if (val < 0) + return val; + } + + if (val) + return GPIO_LINE_DIRECTION_IN; + + return GPIO_LINE_DIRECTION_OUT; + } + + if (omnia_gpios[offset].ctl_cmd) + return GPIO_LINE_DIRECTION_OUT; + + return GPIO_LINE_DIRECTION_IN; +} + +static int omnia_gpio_direction_input(struct gpio_chip *gc, unsigned int offset) +{ + const struct omnia_gpio *gpio = &omnia_gpios[offset]; + struct omnia_mcu *mcu = gpiochip_get_data(gc); + + if (offset == OMNIA_GPIO_PHY_SFP_OFFSET) + return omnia_ctl_cmd(mcu, OMNIA_CMD_EXT_CONTROL, + OMNIA_EXT_CTL_PHY_SFP_AUTO, + OMNIA_EXT_CTL_PHY_SFP_AUTO); + + if (gpio->ctl_cmd) + return -ENOTSUPP; + + return 0; +} + +static int omnia_gpio_direction_output(struct gpio_chip *gc, + unsigned int offset, int value) +{ + const struct omnia_gpio *gpio = &omnia_gpios[offset]; + struct omnia_mcu *mcu = gpiochip_get_data(gc); + u16 val, mask; + + if (!gpio->ctl_cmd) + return -ENOTSUPP; + + mask = BIT(gpio->ctl_bit); + val = value ? mask : 0; + + if (offset == OMNIA_GPIO_PHY_SFP_OFFSET) + mask |= OMNIA_EXT_CTL_PHY_SFP_AUTO; + + return omnia_ctl_cmd(mcu, gpio->ctl_cmd, val, mask); +} + +static int omnia_gpio_get(struct gpio_chip *gc, unsigned int offset) +{ + const struct omnia_gpio *gpio = &omnia_gpios[offset]; + struct omnia_mcu *mcu = gpiochip_get_data(gc); + + /* + * If firmware does not support the new interrupt API, we are informed + * of every change of the status word by an interrupt from MCU and save + * its value in the interrupt service routine. Simply return the saved + * value. + */ + if (gpio->cmd == OMNIA_CMD_GET_STATUS_WORD && + !(mcu->features & OMNIA_FEAT_NEW_INT_API)) + return test_bit(gpio->bit, &mcu->last_status); + + guard(mutex)(&mcu->lock); + + /* + * If firmware does support the new interrupt API, we may have cached + * the value of a GPIO in the interrupt service routine. If not, read + * the relevant bit now. + */ + if (is_int_bit_valid(gpio) && test_bit(gpio->int_bit, &mcu->is_cached)) + return test_bit(gpio->int_bit, &mcu->cached); + + return omnia_cmd_read_bit(mcu->client, gpio->cmd, BIT(gpio->bit)); +} + +static unsigned long * +_relevant_field_for_sts_cmd(u8 cmd, unsigned long *sts, unsigned long *ext_sts, + unsigned long *ext_ctl) +{ + switch (cmd) { + case OMNIA_CMD_GET_STATUS_WORD: + return sts; + case OMNIA_CMD_GET_EXT_STATUS_DWORD: + return ext_sts; + case OMNIA_CMD_GET_EXT_CONTROL_STATUS: + return ext_ctl; + default: + return NULL; + } +} + +static int omnia_gpio_get_multiple(struct gpio_chip *gc, unsigned long *mask, + unsigned long *bits) +{ + unsigned long sts = 0, ext_sts = 0, ext_ctl = 0, *field; + struct omnia_mcu *mcu = gpiochip_get_data(gc); + struct i2c_client *client = mcu->client; + unsigned int i; + int err; + + /* determine which bits to read from the 3 possible commands */ + for_each_set_bit(i, mask, ARRAY_SIZE(omnia_gpios)) { + field = _relevant_field_for_sts_cmd(omnia_gpios[i].cmd, + &sts, &ext_sts, &ext_ctl); + if (!field) + continue; + + __set_bit(omnia_gpios[i].bit, field); + } + + guard(mutex)(&mcu->lock); + + if (mcu->features & OMNIA_FEAT_NEW_INT_API) { + /* read relevant bits from status */ + err = omnia_cmd_read_bits(client, OMNIA_CMD_GET_STATUS_WORD, + sts, &sts); + if (err) + return err; + } else { + /* + * Use status word value cached in the interrupt service routine + * if firmware does not support the new interrupt API. + */ + sts = mcu->last_status; + } + + /* read relevant bits from extended status */ + err = omnia_cmd_read_bits(client, OMNIA_CMD_GET_EXT_STATUS_DWORD, + ext_sts, &ext_sts); + if (err) + return err; + + /* read relevant bits from extended control */ + err = omnia_cmd_read_bits(client, OMNIA_CMD_GET_EXT_CONTROL_STATUS, + ext_ctl, &ext_ctl); + if (err) + return err; + + /* assign relevant bits in result */ + for_each_set_bit(i, mask, ARRAY_SIZE(omnia_gpios)) { + field = _relevant_field_for_sts_cmd(omnia_gpios[i].cmd, + &sts, &ext_sts, &ext_ctl); + if (!field) + continue; + + __assign_bit(i, bits, test_bit(omnia_gpios[i].bit, field)); + } + + return 0; +} + +static void omnia_gpio_set(struct gpio_chip *gc, unsigned int offset, int value) +{ + const struct omnia_gpio *gpio = &omnia_gpios[offset]; + struct omnia_mcu *mcu = gpiochip_get_data(gc); + u16 val, mask; + + if (!gpio->ctl_cmd) + return; + + mask = BIT(gpio->ctl_bit); + val = value ? mask : 0; + + omnia_ctl_cmd(mcu, gpio->ctl_cmd, val, mask); +} + +static void omnia_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask, + unsigned long *bits) +{ + unsigned long ctl = 0, ctl_mask = 0, ext_ctl = 0, ext_ctl_mask = 0; + struct omnia_mcu *mcu = gpiochip_get_data(gc); + unsigned int i; + + for_each_set_bit(i, mask, ARRAY_SIZE(omnia_gpios)) { + unsigned long *field, *field_mask; + u8 bit = omnia_gpios[i].ctl_bit; + + switch (omnia_gpios[i].ctl_cmd) { + case OMNIA_CMD_GENERAL_CONTROL: + field = &ctl; + field_mask = &ctl_mask; + break; + case OMNIA_CMD_EXT_CONTROL: + field = &ext_ctl; + field_mask = &ext_ctl_mask; + break; + default: + field = field_mask = NULL; + break; + } + + if (!field) + continue; + + __set_bit(bit, field_mask); + __assign_bit(bit, field, test_bit(i, bits)); + } + + guard(mutex)(&mcu->lock); + + if (ctl_mask) + omnia_ctl_cmd_locked(mcu, OMNIA_CMD_GENERAL_CONTROL, + ctl, ctl_mask); + + if (ext_ctl_mask) + omnia_ctl_cmd_locked(mcu, OMNIA_CMD_EXT_CONTROL, + ext_ctl, ext_ctl_mask); +} + +static bool omnia_gpio_available(struct omnia_mcu *mcu, + const struct omnia_gpio *gpio) +{ + if (gpio->feat_mask) + return (mcu->features & gpio->feat_mask) == gpio->feat; + + if (gpio->feat) + return mcu->features & gpio->feat; + + return true; +} + +static int omnia_gpio_init_valid_mask(struct gpio_chip *gc, + unsigned long *valid_mask, + unsigned int ngpios) +{ + struct omnia_mcu *mcu = gpiochip_get_data(gc); + + for (unsigned int i = 0; i < ngpios; i++) { + const struct omnia_gpio *gpio = &omnia_gpios[i]; + + if (gpio->cmd || is_int_bit_valid(gpio)) + __assign_bit(i, valid_mask, + omnia_gpio_available(mcu, gpio)); + else + __clear_bit(i, valid_mask); + } + + return 0; +} + +static int omnia_gpio_of_xlate(struct gpio_chip *gc, + const struct of_phandle_args *gpiospec, + u32 *flags) +{ + u32 bank, gpio; + + if (WARN_ON(gpiospec->args_count != 3)) + return -EINVAL; + + if (flags) + *flags = gpiospec->args[2]; + + bank = gpiospec->args[0]; + gpio = gpiospec->args[1]; + + switch (bank) { + case 0: + return gpio < 16 ? gpio : -EINVAL; + case 1: + return gpio < 32 ? 16 + gpio : -EINVAL; + case 2: + return gpio < 16 ? 48 + gpio : -EINVAL; + default: + return -EINVAL; + } +} + +static void omnia_irq_shutdown(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct omnia_mcu *mcu = gpiochip_get_data(gc); + irq_hw_number_t hwirq = irqd_to_hwirq(d); + u8 bit = omnia_gpios[hwirq].int_bit; + + __clear_bit(bit, &mcu->rising); + __clear_bit(bit, &mcu->falling); +} + +static void omnia_irq_mask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct omnia_mcu *mcu = gpiochip_get_data(gc); + irq_hw_number_t hwirq = irqd_to_hwirq(d); + u8 bit = omnia_gpios[hwirq].int_bit; + + if (!omnia_gpios[hwirq].cmd) + __clear_bit(bit, &mcu->rising); + __clear_bit(bit, &mcu->mask); + gpiochip_disable_irq(gc, hwirq); +} + +static void omnia_irq_unmask(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct omnia_mcu *mcu = gpiochip_get_data(gc); + irq_hw_number_t hwirq = irqd_to_hwirq(d); + u8 bit = omnia_gpios[hwirq].int_bit; + + gpiochip_enable_irq(gc, hwirq); + __set_bit(bit, &mcu->mask); + if (!omnia_gpios[hwirq].cmd) + __set_bit(bit, &mcu->rising); +} + +static int omnia_irq_set_type(struct irq_data *d, unsigned int type) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct omnia_mcu *mcu = gpiochip_get_data(gc); + irq_hw_number_t hwirq = irqd_to_hwirq(d); + struct device *dev = &mcu->client->dev; + u8 bit = omnia_gpios[hwirq].int_bit; + + if (!(type & IRQ_TYPE_EDGE_BOTH)) { + dev_err(dev, "irq %u: unsupported type %u\n", d->irq, type); + return -EINVAL; + } + + __assign_bit(bit, &mcu->rising, type & IRQ_TYPE_EDGE_RISING); + __assign_bit(bit, &mcu->falling, type & IRQ_TYPE_EDGE_FALLING); + + return 0; +} + +static void omnia_irq_bus_lock(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct omnia_mcu *mcu = gpiochip_get_data(gc); + + /* nothing to do if MCU firmware does not support new interrupt API */ + if (!(mcu->features & OMNIA_FEAT_NEW_INT_API)) + return; + + mutex_lock(&mcu->lock); +} + +/** + * omnia_mask_interleave - Interleaves the bytes from @rising and @falling + * @dst: the destination u8 array of interleaved bytes + * @rising: rising mask + * @falling: falling mask + * + * Interleaves the little-endian bytes from @rising and @falling words. + * + * If @rising = (r0, r1, r2, r3) and @falling = (f0, f1, f2, f3), the result is + * @dst = (r0, f0, r1, f1, r2, f2, r3, f3). + * + * The MCU receives an interrupt mask and reports a pending interrupt bitmap in + * this interleaved format. The rationale behind this is that the low-indexed + * bits are more important - in many cases, the user will be interested only in + * interrupts with indexes 0 to 7, and so the system can stop reading after + * first 2 bytes (r0, f0), to save time on the slow I2C bus. + * + * Feel free to remove this function and its inverse, omnia_mask_deinterleave, + * and use an appropriate bitmap_*() function once such a function exists. + */ +static void +omnia_mask_interleave(u8 *dst, unsigned long rising, unsigned long falling) +{ + for (unsigned int i = 0; i < sizeof(u32); i++) { + dst[2 * i] = rising >> (8 * i); + dst[2 * i + 1] = falling >> (8 * i); + } +} + +/** + * omnia_mask_deinterleave - Deinterleaves the bytes into @rising and @falling + * @src: the source u8 array containing the interleaved bytes + * @rising: pointer where to store the rising mask gathered from @src + * @falling: pointer where to store the falling mask gathered from @src + * + * This is the inverse function to omnia_mask_interleave. + */ +static void omnia_mask_deinterleave(const u8 *src, unsigned long *rising, + unsigned long *falling) +{ + *rising = *falling = 0; + + for (unsigned int i = 0; i < sizeof(u32); i++) { + *rising |= src[2 * i] << (8 * i); + *falling |= src[2 * i + 1] << (8 * i); + } +} + +static void omnia_irq_bus_sync_unlock(struct irq_data *d) +{ + struct gpio_chip *gc = irq_data_get_irq_chip_data(d); + struct omnia_mcu *mcu = gpiochip_get_data(gc); + struct device *dev = &mcu->client->dev; + u8 cmd[1 + OMNIA_CMD_INT_ARG_LEN]; + unsigned long rising, falling; + int err; + + /* nothing to do if MCU firmware does not support new interrupt API */ + if (!(mcu->features & OMNIA_FEAT_NEW_INT_API)) + return; + + cmd[0] = OMNIA_CMD_SET_INT_MASK; + + rising = mcu->rising & mcu->mask; + falling = mcu->falling & mcu->mask; + + /* interleave the rising and falling bytes into the command arguments */ + omnia_mask_interleave(&cmd[1], rising, falling); + + dev_dbg(dev, "set int mask %8ph\n", &cmd[1]); + + err = omnia_cmd_write(mcu->client, cmd, sizeof(cmd)); + if (err) { + dev_err(dev, "Cannot set mask: %d\n", err); + goto unlock; + } + + /* + * Remember which GPIOs have both rising and falling interrupts enabled. + * For those we will cache their value so that .get() method is faster. + * We also need to forget cached values of GPIOs that aren't cached + * anymore. + */ + mcu->both = rising & falling; + mcu->is_cached &= mcu->both; + +unlock: + mutex_unlock(&mcu->lock); +} + +static const struct irq_chip omnia_mcu_irq_chip = { + .name = "Turris Omnia MCU interrupts", + .irq_shutdown = omnia_irq_shutdown, + .irq_mask = omnia_irq_mask, + .irq_unmask = omnia_irq_unmask, + .irq_set_type = omnia_irq_set_type, + .irq_bus_lock = omnia_irq_bus_lock, + .irq_bus_sync_unlock = omnia_irq_bus_sync_unlock, + .flags = IRQCHIP_IMMUTABLE, + GPIOCHIP_IRQ_RESOURCE_HELPERS, +}; + +static void omnia_irq_init_valid_mask(struct gpio_chip *gc, + unsigned long *valid_mask, + unsigned int ngpios) +{ + struct omnia_mcu *mcu = gpiochip_get_data(gc); + + for (unsigned int i = 0; i < ngpios; i++) { + const struct omnia_gpio *gpio = &omnia_gpios[i]; + + if (is_int_bit_valid(gpio)) + __assign_bit(i, valid_mask, + omnia_gpio_available(mcu, gpio)); + else + __clear_bit(i, valid_mask); + } +} + +static int omnia_irq_init_hw(struct gpio_chip *gc) +{ + struct omnia_mcu *mcu = gpiochip_get_data(gc); + u8 cmd[1 + OMNIA_CMD_INT_ARG_LEN] = {}; + + cmd[0] = OMNIA_CMD_SET_INT_MASK; + + return omnia_cmd_write(mcu->client, cmd, sizeof(cmd)); +} + +/* + * Determine how many bytes we need to read from the reply to the + * OMNIA_CMD_GET_INT_AND_CLEAR command in order to retrieve all unmasked + * interrupts. + */ +static unsigned int +omnia_irq_compute_pending_length(unsigned long rising, unsigned long falling) +{ + return max(omnia_compute_reply_length(rising, true, 0), + omnia_compute_reply_length(falling, true, 1)); +} + +static bool omnia_irq_read_pending_new(struct omnia_mcu *mcu, + unsigned long *pending) +{ + struct device *dev = &mcu->client->dev; + u8 reply[OMNIA_CMD_INT_ARG_LEN] = {}; + unsigned long rising, falling; + unsigned int len; + int err; + + len = omnia_irq_compute_pending_length(mcu->rising & mcu->mask, + mcu->falling & mcu->mask); + if (!len) + return false; + + guard(mutex)(&mcu->lock); + + err = omnia_cmd_read(mcu->client, OMNIA_CMD_GET_INT_AND_CLEAR, reply, + len); + if (err) { + dev_err(dev, "Cannot read pending IRQs: %d\n", err); + return false; + } + + /* deinterleave the reply bytes into rising and falling */ + omnia_mask_deinterleave(reply, &rising, &falling); + + rising &= mcu->mask; + falling &= mcu->mask; + *pending = rising | falling; + + /* cache values for GPIOs that have both edges enabled */ + mcu->is_cached &= ~(rising & falling); + mcu->is_cached |= mcu->both & (rising ^ falling); + mcu->cached = (mcu->cached | rising) & ~falling; + + return true; +} + +static int omnia_read_status_word_old_fw(struct omnia_mcu *mcu, + unsigned long *status) +{ + u16 raw_status; + int err; + + err = omnia_cmd_read_u16(mcu->client, OMNIA_CMD_GET_STATUS_WORD, + &raw_status); + if (err) + return err; + + /* + * Old firmware has a bug wherein it never resets the USB port + * overcurrent bits back to zero. Ignore them. + */ + *status = raw_status & ~(OMNIA_STS_USB30_OVC | OMNIA_STS_USB31_OVC); + + return 0; +} + +static void button_release_emul_fn(struct work_struct *work) +{ + struct omnia_mcu *mcu = container_of(to_delayed_work(work), + struct omnia_mcu, + button_release_emul_work); + + mcu->button_pressed_emul = false; + generic_handle_irq_safe(mcu->client->irq); +} + +static void +fill_int_from_sts(unsigned long *rising, unsigned long *falling, + unsigned long rising_sts, unsigned long falling_sts, + unsigned long sts_bit, unsigned long int_bit) +{ + if (rising_sts & sts_bit) + *rising |= int_bit; + if (falling_sts & sts_bit) + *falling |= int_bit; +} + +static bool omnia_irq_read_pending_old(struct omnia_mcu *mcu, + unsigned long *pending) +{ + unsigned long status, rising_sts, falling_sts, rising, falling; + struct device *dev = &mcu->client->dev; + int err; + + guard(mutex)(&mcu->lock); + + err = omnia_read_status_word_old_fw(mcu, &status); + if (err) { + dev_err(dev, "Cannot read pending IRQs: %d\n", err); + return false; + } + + /* + * The old firmware triggers an interrupt whenever status word changes, + * but does not inform about which bits rose or fell. We need to compute + * this here by comparing with the last status word value. + * + * The OMNIA_STS_BUTTON_PRESSED bit needs special handling, because the + * old firmware clears the OMNIA_STS_BUTTON_PRESSED bit on successful + * completion of the OMNIA_CMD_GET_STATUS_WORD command, resulting in + * another interrupt: + * - first we get an interrupt, we read the status word where + * OMNIA_STS_BUTTON_PRESSED is present, + * - MCU clears the OMNIA_STS_BUTTON_PRESSED bit because we read the + * status word, + * - we get another interrupt because the status word changed again + * (the OMNIA_STS_BUTTON_PRESSED bit was cleared). + * + * The gpiolib-cdev, gpiolib-sysfs and gpio-keys input driver all call + * the gpiochip's .get() method after an edge event on a requested GPIO + * occurs. + * + * We ensure that the .get() method reads 1 for the button GPIO for some + * time. + */ + + if (status & OMNIA_STS_BUTTON_PRESSED) { + mcu->button_pressed_emul = true; + mod_delayed_work(system_wq, &mcu->button_release_emul_work, + msecs_to_jiffies(FRONT_BUTTON_RELEASE_DELAY_MS)); + } else if (mcu->button_pressed_emul) { + status |= OMNIA_STS_BUTTON_PRESSED; + } + + rising_sts = ~mcu->last_status & status; + falling_sts = mcu->last_status & ~status; + + mcu->last_status = status; + + /* + * Fill in the relevant interrupt bits from status bits for CARD_DET, + * MSATA_IND and BUTTON_PRESSED. + */ + rising = 0; + falling = 0; + fill_int_from_sts(&rising, &falling, rising_sts, falling_sts, + OMNIA_STS_CARD_DET, OMNIA_INT_CARD_DET); + fill_int_from_sts(&rising, &falling, rising_sts, falling_sts, + OMNIA_STS_MSATA_IND, OMNIA_INT_MSATA_IND); + fill_int_from_sts(&rising, &falling, rising_sts, falling_sts, + OMNIA_STS_BUTTON_PRESSED, OMNIA_INT_BUTTON_PRESSED); + + /* Use only bits that are enabled */ + rising &= mcu->rising & mcu->mask; + falling &= mcu->falling & mcu->mask; + *pending = rising | falling; + + return true; +} + +static bool omnia_irq_read_pending(struct omnia_mcu *mcu, + unsigned long *pending) +{ + if (mcu->features & OMNIA_FEAT_NEW_INT_API) + return omnia_irq_read_pending_new(mcu, pending); + else + return omnia_irq_read_pending_old(mcu, pending); +} + +static irqreturn_t omnia_irq_thread_handler(int irq, void *dev_id) +{ + struct omnia_mcu *mcu = dev_id; + struct irq_domain *domain; + unsigned long pending; + unsigned int i; + + if (!omnia_irq_read_pending(mcu, &pending)) + return IRQ_NONE; + + domain = mcu->gc.irq.domain; + + for_each_set_bit(i, &pending, 32) { + unsigned int nested_irq; + + nested_irq = irq_find_mapping(domain, omnia_int_to_gpio_idx[i]); + + handle_nested_irq(nested_irq); + } + + return IRQ_RETVAL(pending); +} + +static const char * const front_button_modes[] = { "mcu", "cpu" }; + +static ssize_t front_button_mode_show(struct device *dev, + struct device_attribute *a, char *buf) +{ + struct omnia_mcu *mcu = dev_get_drvdata(dev); + int val; + + if (mcu->features & OMNIA_FEAT_NEW_INT_API) { + val = omnia_cmd_read_bit(mcu->client, OMNIA_CMD_GET_STATUS_WORD, + OMNIA_STS_BUTTON_MODE); + if (val < 0) + return val; + } else { + val = !!(mcu->last_status & OMNIA_STS_BUTTON_MODE); + } + + return sysfs_emit(buf, "%s\n", front_button_modes[val]); +} + +static ssize_t front_button_mode_store(struct device *dev, + struct device_attribute *a, + const char *buf, size_t count) +{ + struct omnia_mcu *mcu = dev_get_drvdata(dev); + int err, i; + + i = sysfs_match_string(front_button_modes, buf); + if (i < 0) + return i; + + err = omnia_ctl_cmd_locked(mcu, OMNIA_CMD_GENERAL_CONTROL, + i ? OMNIA_CTL_BUTTON_MODE : 0, + OMNIA_CTL_BUTTON_MODE); + if (err) + return err; + + return count; +} +static DEVICE_ATTR_RW(front_button_mode); + +static struct attribute *omnia_mcu_gpio_attrs[] = { + &dev_attr_front_button_mode.attr, + NULL +}; + +const struct attribute_group omnia_mcu_gpio_group = { + .attrs = omnia_mcu_gpio_attrs, +}; + +int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu) +{ + bool new_api = mcu->features & OMNIA_FEAT_NEW_INT_API; + struct device *dev = &mcu->client->dev; + unsigned long irqflags; + int err; + + err = devm_mutex_init(dev, &mcu->lock); + if (err) + return err; + + mcu->gc.request = omnia_gpio_request; + mcu->gc.get_direction = omnia_gpio_get_direction; + mcu->gc.direction_input = omnia_gpio_direction_input; + mcu->gc.direction_output = omnia_gpio_direction_output; + mcu->gc.get = omnia_gpio_get; + mcu->gc.get_multiple = omnia_gpio_get_multiple; + mcu->gc.set = omnia_gpio_set; + mcu->gc.set_multiple = omnia_gpio_set_multiple; + mcu->gc.init_valid_mask = omnia_gpio_init_valid_mask; + mcu->gc.can_sleep = true; + mcu->gc.names = omnia_mcu_gpio_templates; + mcu->gc.base = -1; + mcu->gc.ngpio = ARRAY_SIZE(omnia_gpios); + mcu->gc.label = "Turris Omnia MCU GPIOs"; + mcu->gc.parent = dev; + mcu->gc.owner = THIS_MODULE; + mcu->gc.of_gpio_n_cells = 3; + mcu->gc.of_xlate = omnia_gpio_of_xlate; + + gpio_irq_chip_set_chip(&mcu->gc.irq, &omnia_mcu_irq_chip); + /* This will let us handle the parent IRQ in the driver */ + mcu->gc.irq.parent_handler = NULL; + mcu->gc.irq.num_parents = 0; + mcu->gc.irq.parents = NULL; + mcu->gc.irq.default_type = IRQ_TYPE_NONE; + mcu->gc.irq.handler = handle_bad_irq; + mcu->gc.irq.threaded = true; + if (new_api) + mcu->gc.irq.init_hw = omnia_irq_init_hw; + mcu->gc.irq.init_valid_mask = omnia_irq_init_valid_mask; + + err = devm_gpiochip_add_data(dev, &mcu->gc, mcu); + if (err) + return dev_err_probe(dev, err, "Cannot add GPIO chip\n"); + + /* + * Before requesting the interrupt, if firmware does not support the new + * interrupt API, we need to cache the value of the status word, so that + * when it changes, we may compare the new value with the cached one in + * the interrupt handler. + */ + if (!new_api) { + err = omnia_read_status_word_old_fw(mcu, &mcu->last_status); + if (err) + return dev_err_probe(dev, err, + "Cannot read status word\n"); + + INIT_DELAYED_WORK(&mcu->button_release_emul_work, + button_release_emul_fn); + } + + irqflags = IRQF_ONESHOT; + if (new_api) + irqflags |= IRQF_TRIGGER_LOW; + else + irqflags |= IRQF_TRIGGER_FALLING; + + err = devm_request_threaded_irq(dev, mcu->client->irq, NULL, + omnia_irq_thread_handler, irqflags, + "turris-omnia-mcu", mcu); + if (err) + return dev_err_probe(dev, err, "Cannot request IRQ\n"); + + if (!new_api) { + /* + * The button_release_emul_work has to be initialized before the + * thread is requested, and on driver remove it needs to be + * canceled before the thread is freed. Therefore we can't use + * devm_delayed_work_autocancel() directly, because the order + * devm_delayed_work_autocancel(); + * devm_request_threaded_irq(); + * would cause improper release order: + * free_irq(); + * cancel_delayed_work_sync(); + * Instead we first initialize the work above, and only now + * after IRQ is requested we add the work devm action. + */ + err = devm_add_action(dev, devm_delayed_work_drop, + &mcu->button_release_emul_work); + if (err) + return err; + } + + return 0; +} |