1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * CZ.NIC's Turris Omnia MCU driver
4 *
5 * 2024 by Marek Behún <kabel@kernel.org>
6 */
7
8 #ifndef __TURRIS_OMNIA_MCU_H
9 #define __TURRIS_OMNIA_MCU_H
10
11 #include <linux/completion.h>
12 #include <linux/gpio/driver.h>
13 #include <linux/hw_random.h>
14 #include <linux/if_ether.h>
15 #include <linux/interrupt.h>
16 #include <linux/mutex.h>
17 #include <linux/types.h>
18 #include <linux/watchdog.h>
19 #include <linux/workqueue.h>
20
21 enum {
22 OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN = 1 + 32,
23 OMNIA_MCU_CRYPTO_SIGNATURE_LEN = 64,
24 };
25
26 struct i2c_client;
27 struct rtc_device;
28
29 /**
30 * struct omnia_mcu - driver private data structure
31 * @client: I2C client
32 * @type: MCU type (STM32, GD32, MKL, or unknown)
33 * @features: bitmap of features supported by the MCU firmware
34 * @board_serial_number: board serial number, if stored in MCU
35 * @board_first_mac: board first MAC address, if stored in MCU
36 * @board_revision: board revision, if stored in MCU
37 * @gc: GPIO chip
38 * @lock: mutex to protect internal GPIO chip state
39 * @mask: bitmap of masked IRQs
40 * @rising: bitmap of rising edge IRQs
41 * @falling: bitmap of falling edge IRQs
42 * @both: bitmap of both edges IRQs
43 * @cached: bitmap of cached IRQ line values (when an IRQ line is configured for
44 * both edges, we cache the corresponding GPIO values in the IRQ
45 * handler)
46 * @is_cached: bitmap of which IRQ line values are cached
47 * @button_release_emul_work: front button release emulation work, used with old MCU firmware
48 * versions which did not send button release events, only button press
49 * events
50 * @last_status: cached value of the status word, to be compared with new value to
51 * determine which interrupt events occurred, used with old MCU
52 * firmware versions which only informed that the status word changed,
53 * but not which bits of the status word changed
54 * @button_pressed_emul: the front button is still emulated to be pressed
55 * @rtcdev: RTC device, does not actually count real-time, the device is only
56 * used for the RTC alarm mechanism, so that the board can be
57 * configured to wake up from poweroff state at a specific time
58 * @rtc_alarm: RTC alarm that was set for the board to wake up on, in MCU time
59 * (seconds since last MCU reset)
60 * @front_button_poweron: the front button should power on the device after it is powered off
61 * @wdt: watchdog driver structure
62 * @trng: RNG driver structure
63 * @trng_entropy_ready: RNG entropy ready completion
64 * @msg_signed: message signed completion
65 * @sign_lock: mutex to protect message signing state
66 * @sign_requested: flag indicating that message signing was requested but not completed
67 * @sign_err: message signing error number, filled in interrupt handler
68 * @signature: message signing signature, filled in interrupt handler
69 * @board_public_key: board public key, if stored in MCU
70 */
71 struct omnia_mcu {
72 struct i2c_client *client;
73 const char *type;
74 u32 features;
75
76 u64 board_serial_number;
77 u8 board_first_mac[ETH_ALEN];
78 u8 board_revision;
79
80 #ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
81 struct gpio_chip gc;
82 struct mutex lock;
83 unsigned long mask, rising, falling, both, cached, is_cached;
84 struct delayed_work button_release_emul_work;
85 unsigned long last_status;
86 bool button_pressed_emul;
87 #endif
88
89 #ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
90 struct rtc_device *rtcdev;
91 u32 rtc_alarm;
92 bool front_button_poweron;
93 #endif
94
95 #ifdef CONFIG_TURRIS_OMNIA_MCU_WATCHDOG
96 struct watchdog_device wdt;
97 #endif
98
99 #ifdef CONFIG_TURRIS_OMNIA_MCU_TRNG
100 struct hwrng trng;
101 struct completion trng_entropy_ready;
102 #endif
103
104 #ifdef CONFIG_TURRIS_OMNIA_MCU_KEYCTL
105 struct completion msg_signed;
106 struct mutex sign_lock;
107 bool sign_requested;
108 int sign_err;
109 u8 signature[OMNIA_MCU_CRYPTO_SIGNATURE_LEN];
110 u8 board_public_key[OMNIA_MCU_CRYPTO_PUBLIC_KEY_LEN];
111 #endif
112 };
113
114 #ifdef CONFIG_TURRIS_OMNIA_MCU_GPIO
115 extern const struct attribute_group omnia_mcu_gpio_group;
116 int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu);
117 int omnia_mcu_request_irq(struct omnia_mcu *mcu, u32 spec,
118 irq_handler_t thread_fn, const char *devname);
119 #else
omnia_mcu_register_gpiochip(struct omnia_mcu * mcu)120 static inline int omnia_mcu_register_gpiochip(struct omnia_mcu *mcu)
121 {
122 return 0;
123 }
124 #endif
125
126 #ifdef CONFIG_TURRIS_OMNIA_MCU_KEYCTL
127 int omnia_mcu_register_keyctl(struct omnia_mcu *mcu);
128 #else
omnia_mcu_register_keyctl(struct omnia_mcu * mcu)129 static inline int omnia_mcu_register_keyctl(struct omnia_mcu *mcu)
130 {
131 return 0;
132 }
133 #endif
134
135 #ifdef CONFIG_TURRIS_OMNIA_MCU_SYSOFF_WAKEUP
136 extern const struct attribute_group omnia_mcu_poweroff_group;
137 int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu);
138 #else
omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu * mcu)139 static inline int omnia_mcu_register_sys_off_and_wakeup(struct omnia_mcu *mcu)
140 {
141 return 0;
142 }
143 #endif
144
145 #ifdef CONFIG_TURRIS_OMNIA_MCU_TRNG
146 int omnia_mcu_register_trng(struct omnia_mcu *mcu);
147 #else
omnia_mcu_register_trng(struct omnia_mcu * mcu)148 static inline int omnia_mcu_register_trng(struct omnia_mcu *mcu)
149 {
150 return 0;
151 }
152 #endif
153
154 #ifdef CONFIG_TURRIS_OMNIA_MCU_WATCHDOG
155 int omnia_mcu_register_watchdog(struct omnia_mcu *mcu);
156 #else
omnia_mcu_register_watchdog(struct omnia_mcu * mcu)157 static inline int omnia_mcu_register_watchdog(struct omnia_mcu *mcu)
158 {
159 return 0;
160 }
161 #endif
162
163 #endif /* __TURRIS_OMNIA_MCU_H */
164