1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Generation of tables for particular device types
4  *
5  * Copyright 2019 Google LLC
6  * Mostly taken from coreboot file of the same name
7  */
8 
9 #ifndef __ACPI_DEVICE_H
10 #define __ACPI_DEVICE_H
11 
12 #include <i2c.h>
13 #include <irq.h>
14 #include <spi.h>
15 #include <asm-generic/gpio.h>
16 #include <linux/bitops.h>
17 
18 struct acpi_ctx;
19 struct gpio_desc;
20 struct irq;
21 struct udevice;
22 
23 /* ACPI descriptor values for common descriptors: SERIAL_BUS means I2C */
24 #define ACPI_DESCRIPTOR_LARGE		BIT(7)
25 #define ACPI_DESCRIPTOR_REGISTER	(ACPI_DESCRIPTOR_LARGE | 2)
26 #define ACPI_DESCRIPTOR_INTERRUPT	(ACPI_DESCRIPTOR_LARGE | 9)
27 #define ACPI_DESCRIPTOR_GPIO		(ACPI_DESCRIPTOR_LARGE | 12)
28 #define ACPI_DESCRIPTOR_SERIAL_BUS	(ACPI_DESCRIPTOR_LARGE | 14)
29 
30 /* Length of a full path to an ACPI device */
31 #define ACPI_PATH_MAX		30
32 
33 /* UUID for an I2C _DSM method */
34 #define ACPI_DSM_I2C_HID_UUID	"3cdff6f7-4267-4555-ad05-b30a3d8938de"
35 
36 /* Values that can be returned for ACPI device _STA method */
37 enum acpi_dev_status {
38 	ACPI_DSTATUS_PRESENT		= BIT(0),
39 	ACPI_DSTATUS_ENABLED		= BIT(1),
40 	ACPI_DSTATUS_SHOW_IN_UI		= BIT(2),
41 	ACPI_DSTATUS_OK			= BIT(3),
42 	ACPI_DSTATUS_HAS_BATTERY	= BIT(4),
43 
44 	ACPI_DSTATUS_ALL_OFF	= 0,
45 	ACPI_DSTATUS_HIDDEN_ON	= ACPI_DSTATUS_PRESENT | ACPI_DSTATUS_ENABLED |
46 		ACPI_DSTATUS_OK,
47 	ACPI_DSTATUS_ALL_ON	= ACPI_DSTATUS_HIDDEN_ON |
48 		ACPI_DSTATUS_SHOW_IN_UI,
49 };
50 
51 /** enum acpi_irq_mode - edge/level trigger mode */
52 enum acpi_irq_mode {
53 	ACPI_IRQ_EDGE_TRIGGERED,
54 	ACPI_IRQ_LEVEL_TRIGGERED,
55 };
56 
57 /**
58  * enum acpi_irq_polarity - polarity of interrupt
59  *
60  * @ACPI_IRQ_ACTIVE_LOW - for ACPI_IRQ_EDGE_TRIGGERED this means falling edge
61  * @ACPI_IRQ_ACTIVE_HIGH - for ACPI_IRQ_EDGE_TRIGGERED this means rising edge
62  * @ACPI_IRQ_ACTIVE_BOTH - not meaningful for ACPI_IRQ_EDGE_TRIGGERED
63  */
64 enum acpi_irq_polarity {
65 	ACPI_IRQ_ACTIVE_LOW,
66 	ACPI_IRQ_ACTIVE_HIGH,
67 	ACPI_IRQ_ACTIVE_BOTH,
68 };
69 
70 /**
71  * enum acpi_irq_shared - whether interrupt is shared or not
72  *
73  * @ACPI_IRQ_EXCLUSIVE: only this device uses the interrupt
74  * @ACPI_IRQ_SHARED: other devices may use this interrupt
75  */
76 enum acpi_irq_shared {
77 	ACPI_IRQ_EXCLUSIVE,
78 	ACPI_IRQ_SHARED,
79 };
80 
81 /** enum acpi_irq_wake - indicates whether this interrupt can wake the device */
82 enum acpi_irq_wake {
83 	ACPI_IRQ_NO_WAKE,
84 	ACPI_IRQ_WAKE,
85 };
86 
87 /**
88  * struct acpi_irq - representation of an ACPI interrupt
89  *
90  * @pin: ACPI pin that is monitored for the interrupt
91  * @mode: Edge/level triggering
92  * @polarity: Interrupt polarity
93  * @shared: Whether interrupt is shared or not
94  * @wake: Whether interrupt can wake the device from sleep
95  */
96 struct acpi_irq {
97 	unsigned int pin;
98 	enum acpi_irq_mode mode;
99 	enum acpi_irq_polarity polarity;
100 	enum acpi_irq_shared shared;
101 	enum acpi_irq_wake wake;
102 };
103 
104 /**
105  * enum acpi_gpio_type - type of the descriptor
106  *
107  * @ACPI_GPIO_TYPE_INTERRUPT: GpioInterrupt
108  * @ACPI_GPIO_TYPE_IO: GpioIo
109  */
110 enum acpi_gpio_type {
111 	ACPI_GPIO_TYPE_INTERRUPT,
112 	ACPI_GPIO_TYPE_IO,
113 };
114 
115 /**
116  * enum acpi_gpio_pull - pull direction
117  *
118  * @ACPI_GPIO_PULL_DEFAULT: Use default value for pin
119  * @ACPI_GPIO_PULL_UP: Pull up
120  * @ACPI_GPIO_PULL_DOWN: Pull down
121  * @ACPI_GPIO_PULL_NONE: No pullup/pulldown
122  */
123 enum acpi_gpio_pull {
124 	ACPI_GPIO_PULL_DEFAULT,
125 	ACPI_GPIO_PULL_UP,
126 	ACPI_GPIO_PULL_DOWN,
127 	ACPI_GPIO_PULL_NONE,
128 };
129 
130 /**
131  * enum acpi_gpio_io_restrict - controls input/output of pin
132  *
133  * @ACPI_GPIO_IO_RESTRICT_NONE: no restrictions
134  * @ACPI_GPIO_IO_RESTRICT_INPUT: input only (no output)
135  * @ACPI_GPIO_IO_RESTRICT_OUTPUT: output only (no input)
136  * @ACPI_GPIO_IO_RESTRICT_PRESERVE: preserve settings when driver not active
137  */
138 enum acpi_gpio_io_restrict {
139 	ACPI_GPIO_IO_RESTRICT_NONE,
140 	ACPI_GPIO_IO_RESTRICT_INPUT,
141 	ACPI_GPIO_IO_RESTRICT_OUTPUT,
142 	ACPI_GPIO_IO_RESTRICT_PRESERVE,
143 };
144 
145 /** enum acpi_gpio_polarity - controls the GPIO polarity */
146 enum acpi_gpio_polarity {
147 	ACPI_GPIO_ACTIVE_HIGH = 0,
148 	ACPI_GPIO_ACTIVE_LOW = 1,
149 };
150 
151 #define ACPI_GPIO_REVISION_ID		1
152 #define ACPI_GPIO_MAX_PINS		2
153 
154 /**
155  * struct acpi_gpio - representation of an ACPI GPIO
156  *
157  * @pin_count: Number of pins represented
158  * @pins: List of pins
159  * @pin0_addr: Address in memory of the control registers for pin 0. This is
160  *   used when generating ACPI tables
161  * @type: GPIO type
162  * @pull: Pullup/pulldown setting
163  * @resource: Resource name for this GPIO controller
164  * For GpioInt:
165  * @interrupt_debounce_timeout: Debounce timeout in units of 10us
166  * @irq: Interrupt
167  *
168  * For GpioIo:
169  * @output_drive_strength: Drive strength in units of 10uA
170  * @io_shared; true if GPIO is shared
171  * @io_restrict: I/O restriction setting
172  * @polarity: GPIO polarity
173  *
174  * Note that GpioIo() doesn't have any means of Active Low / High setting, so a
175  * _DSD must be provided to mitigate this. This parameter does not make sense
176  * for GpioInt() since it has its own means to define it.
177  *
178  * GpioIo() doesn't properly communicate the initial state of the output pin,
179  * thus Linux assumes the simple rule:
180  *
181  * Pull Bias       Polarity      Requested...
182  *
183  * Implicit        x             AS IS (assumed firmware configured for us)
184  * Explicit        x (no _DSD)   as Pull Bias (Up == High, Down == Low),
185  *                               assuming non-active (Polarity = !Pull Bias)
186  *
187  * Down            Low           as low, assuming active
188  * Down            High          as low, assuming non-active
189  * Up              Low           as high, assuming non-active
190  * Up              High          as high, assuming active
191  *
192  * GpioIo() can be used as interrupt and in this case the IoRestriction mustn't
193  * be OutputOnly. It also requires active_low flag from _DSD in cases where it's
194  * needed (better to always provide than rely on above assumption made on OS
195  * level).
196  */
197 struct acpi_gpio {
198 	int pin_count;
199 	u16 pins[ACPI_GPIO_MAX_PINS];
200 	ulong pin0_addr;
201 
202 	enum acpi_gpio_type type;
203 	enum acpi_gpio_pull pull;
204 	char resource[ACPI_PATH_MAX];
205 
206 	/* GpioInt */
207 	u16 interrupt_debounce_timeout;
208 	struct acpi_irq irq;
209 
210 	/* GpioIo */
211 	u16 output_drive_strength;
212 	bool io_shared;
213 	enum acpi_gpio_io_restrict io_restrict;
214 	enum acpi_gpio_polarity polarity;
215 };
216 
217 /* ACPI Descriptors for Serial Bus interfaces */
218 #define ACPI_SERIAL_BUS_TYPE_I2C		1
219 #define ACPI_SERIAL_BUS_TYPE_SPI		2
220 #define ACPI_I2C_SERIAL_BUS_REVISION_ID		1 /* TODO: upgrade to 2 */
221 #define ACPI_I2C_TYPE_SPECIFIC_REVISION_ID	1
222 #define ACPI_SPI_SERIAL_BUS_REVISION_ID		1
223 #define ACPI_SPI_TYPE_SPECIFIC_REVISION_ID	1
224 
225 /**
226  * struct acpi_i2c - representation of an ACPI I2C device
227  *
228  * @address: 7-bit or 10-bit I2C address
229  * @mode_10bit: Which address size is used
230  * @speed: Bus speed in Hz
231  * @resource: Resource name for the I2C controller
232  */
233 struct acpi_i2c {
234 	u16 address;
235 	enum i2c_address_mode mode_10bit;
236 	enum i2c_speed_rate speed;
237 	const char *resource;
238 };
239 
240 /**
241  * struct acpi_spi - representation of an ACPI SPI device
242  *
243  * @device_select: Chip select used by this device (typically 0)
244  * @device_select_polarity: Polarity for the device
245  * @wire_mode: Number of wires used for SPI
246  * @speed: Bus speed in Hz
247  * @data_bit_length: Word length for SPI (typically 8)
248  * @clock_phase: Clock phase to capture data
249  * @clock_polarity: Bus polarity
250  * @resource: Resource name for the SPI controller
251  */
252 struct acpi_spi {
253 	u16 device_select;
254 	enum spi_polarity device_select_polarity;
255 	enum spi_wire_mode wire_mode;
256 	unsigned int speed;
257 	u8 data_bit_length;
258 	enum spi_clock_phase clock_phase;
259 	enum spi_polarity clock_polarity;
260 	const char *resource;
261 };
262 
263 /**
264  * struct acpi_i2c_priv - Information read from device tree
265  *
266  * This is used by devices which want to specify various pieces of ACPI
267  * information, including power control. It allows a generic function to
268  * generate the information for ACPI, based on device-tree properties.
269  *
270  * @disable_gpio_export_in_crs: Don't export GPIOs in the CRS
271  * @reset_gpio: GPIO used to assert reset to the device
272  * @enable_gpio: GPIO used to enable the device
273  * @stop_gpio: GPIO used to stop the device
274  * @irq_gpio: GPIO used for interrupt (if @irq is not used)
275  * @irq: IRQ used for interrupt (if @irq_gpio is not used)
276  * @hid: _HID value for device (required)
277  * @uid: _UID value for device
278  * @desc: _DDN value for device
279  * @wake: Wake event, e.g. GPE0_DW1_15; 0 if none
280  * @property_count: Number of other DSD properties (currently always 0)
281  * @probed: true set set 'linux,probed' property
282  * @compat_string: Device tree compatible string to report through ACPI
283  * @has_power_resource: true if this device has a power resource
284  * @reset_delay_ms: Delay after de-asserting reset, in ms
285  * @reset_off_delay_ms: Delay after asserting reset (during power off)
286  * @enable_delay_ms: Delay after asserting enable
287  * @enable_off_delay_ms: Delay after de-asserting enable (during power off)
288  * @stop_delay_ms: Delay after de-aserting stop
289  * @stop_off_delay_ms: Delay after asserting stop (during power off)
290  * @hid_desc_reg_offset: HID register offset (for Human Interface Devices)
291  */
292 struct acpi_i2c_priv {
293 	bool disable_gpio_export_in_crs;
294 	struct gpio_desc reset_gpio;
295 	struct gpio_desc enable_gpio;
296 	struct gpio_desc irq_gpio;
297 	struct gpio_desc stop_gpio;
298 	struct irq irq;
299 	const char *hid;
300 	u32 uid;
301 	const char *desc;
302 	u32 wake;
303 	u32 property_count;
304 	bool probed;
305 	const char *compat_string;
306 	bool has_power_resource;
307 	u32 reset_delay_ms;
308 	u32 reset_off_delay_ms;
309 	u32 enable_delay_ms;
310 	u32 enable_off_delay_ms;
311 	u32 stop_delay_ms;
312 	u32 stop_off_delay_ms;
313 	u32 hid_desc_reg_offset;
314 };
315 
316 /**
317  * acpi_device_path() - Get the full path to an ACPI device
318  *
319  * This gets the full path in the form XXXX.YYYY.ZZZZ where XXXX is the root
320  * and ZZZZ is the device. All parent devices are added to the path.
321  *
322  * @dev: Device to check
323  * @buf: Buffer to place the path in (should be ACPI_PATH_MAX long)
324  * @maxlen: Size of buffer (typically ACPI_PATH_MAX)
325  * @return 0 if OK, -ve on error
326  */
327 int acpi_device_path(const struct udevice *dev, char *buf, int maxlen);
328 
329 /**
330  * acpi_device_scope() - Get the scope of an ACPI device
331  *
332  * This gets the scope which is the full path of the parent device, as per
333  * acpi_device_path().
334  *
335  * @dev: Device to check
336  * @buf: Buffer to place the path in (should be ACPI_PATH_MAX long)
337  * @maxlen: Size of buffer (typically ACPI_PATH_MAX)
338  * @return 0 if OK, -EINVAL if the device has no parent, other -ve on other
339  *	error
340  */
341 int acpi_device_scope(const struct udevice *dev, char *scope, int maxlen);
342 
343 /**
344  * acpi_device_status() - Get the status of a device
345  *
346  * This currently just returns ACPI_DSTATUS_ALL_ON. It does not support
347  * inactive or hidden devices.
348  *
349  * @dev: Device to check
350  * @return device status, as ACPI_DSTATUS_...
351  */
352 enum acpi_dev_status acpi_device_status(const struct udevice *dev);
353 
354 /**
355  * acpi_device_write_interrupt_irq() - Write an interrupt descriptor
356  *
357  * This writes an ACPI interrupt descriptor for the given interrupt, converting
358  * fields as needed.
359  *
360  * @ctx: ACPI context pointer
361  * @req_irq: Interrupt to output
362  * @return IRQ pin number if OK, -ve on error
363  */
364 int acpi_device_write_interrupt_irq(struct acpi_ctx *ctx,
365 				    const struct irq *req_irq);
366 
367 /**
368  * acpi_device_write_gpio() - Write GpioIo() or GpioInt() descriptor
369  *
370  * @gpio: GPIO information to write
371  * @return GPIO pin number of first GPIO if OK, -ve on error
372  */
373 int acpi_device_write_gpio(struct acpi_ctx *ctx, const struct acpi_gpio *gpio);
374 
375 /**
376  * acpi_device_write_gpio_desc() - Write a GPIO to ACPI
377  *
378  * This creates a GPIO descriptor for a GPIO, including information ACPI needs
379  * to use it.
380  *
381  * @ctx: ACPI context pointer
382  * @desc: GPIO to write
383  * @return 0 if OK, -ve on error
384  */
385 int acpi_device_write_gpio_desc(struct acpi_ctx *ctx,
386 				const struct gpio_desc *desc);
387 
388 /**
389  * acpi_device_write_interrupt_or_gpio() - Write interrupt or GPIO to ACPI
390  *
391  * This reads an interrupt from the device tree "interrupts-extended" property,
392  * if available. If not it reads the first GPIO with the name @prop.
393  *
394  * If an interrupt is found, an ACPI interrupt descriptor is written to the ACPI
395  * output. If not, but if a GPIO is found, a GPIO descriptor is written.
396  *
397  * @return irq or GPIO pin number if OK, -ve if neither an interrupt nor a GPIO
398  *	could be found, or some other error occurred
399  */
400 int acpi_device_write_interrupt_or_gpio(struct acpi_ctx *ctx,
401 					struct udevice *dev, const char *prop);
402 
403 /**
404  * acpi_device_write_dsm_i2c_hid() - Write a device-specific method for HID
405  *
406  * This writes a DSM for an I2C Human-Interface Device based on the config
407  * provided
408  *
409  * @hid_desc_reg_offset: HID register offset
410  */
411 int acpi_device_write_dsm_i2c_hid(struct acpi_ctx *ctx,
412 				  int hid_desc_reg_offset);
413 
414 /**
415  * acpi_device_write_i2c_dev() - Write an I2C device to ACPI
416  *
417  * This creates a I2cSerialBusV2 descriptor for an I2C device, including
418  * information ACPI needs to use it.
419  *
420  * @ctx: ACPI context pointer
421  * @dev: I2C device to write
422  * @return I2C address of device if OK, -ve on error
423  */
424 int acpi_device_write_i2c_dev(struct acpi_ctx *ctx, const struct udevice *dev);
425 
426 /**
427  * acpi_device_write_spi_dev() - Write a SPI device to ACPI
428  *
429  * This writes a serial bus descriptor for the SPI device so that ACPI can use
430  * it
431  *
432  * @ctx: ACPI context pointer
433  * @dev: SPI device to write
434  * @return 0 if OK, -ve on error
435  */
436 int acpi_device_write_spi_dev(struct acpi_ctx *ctx, const struct udevice *dev);
437 
438 /**
439  * acpi_device_add_power_res() - Add a basic PowerResource block for a device
440  *
441  * This includes GPIOs to control enable, reset and stop operation of the
442  * device. Each GPIO is optional, but at least one must be provided.
443  * This can be applied to any device that has power control, so is fairly
444  * generic.
445  *
446  * Reset - Put the device into / take the device out of reset.
447  * Enable - Enable / disable power to device.
448  * Stop - Stop / start operation of device.
449  *
450  * @ctx: ACPI context pointer
451  * @tx_state_val: Mask to use to toggle the TX state on the GPIO pin, e,g.
452  *	PAD_CFG0_TX_STATE
453  * @dw0_read: Name to use to read dw0, e.g. "\\_SB.GPC0"
454  * @dw0_write: Name to use to read dw0, e.g. "\\_SB.SPC0"
455  * @reset_gpio: GPIO used to take device out of reset or to put it into reset
456  * @reset_delay_ms: Delay to be inserted after device is taken out of reset
457  *	(_ON method delay)
458  * @reset_off_delay_ms: Delay to be inserted after device is put into reset
459  *	(_OFF method delay)
460  * @enable_gpio: GPIO used to enable device
461  * @enable_delay_ms: Delay to be inserted after device is enabled
462  * @enable_off_delay_ms: Delay to be inserted after device is disabled
463  *	(_OFF method delay)
464  * @stop_gpio: GPIO used to stop operation of device
465  * @stop_delay_ms: Delay to be inserted after disabling stop (_ON method delay)
466  * @stop_off_delay_ms: Delay to be inserted after enabling stop.
467  *	(_OFF method delay)
468  *
469  * @return 0 if OK, -ve if at least one GPIO is not provided
470  */
471 int acpi_device_add_power_res(struct acpi_ctx *ctx, u32 tx_state_val,
472 			      const char *dw0_read, const char *dw0_write,
473 			      const struct gpio_desc *reset_gpio,
474 			      uint reset_delay_ms, uint reset_off_delay_ms,
475 			      const struct gpio_desc *enable_gpio,
476 			      uint enable_delay_ms, uint enable_off_delay_ms,
477 			      const struct gpio_desc *stop_gpio,
478 			      uint stop_delay_ms, uint stop_off_delay_ms);
479 
480 /**
481  * acpi_device_infer_name() - Infer the name from its uclass or parent
482  *
483  * Many ACPI devices have a standard name that can be inferred from the uclass
484  * they are in, or the uclass of their parent. These rules are implemented in
485  * this function. It attempts to produce a name for a device based on these
486  * rules.
487  *
488  * NOTE: This currently supports only x86 devices. Feel free to enhance it for
489  * other architectures as needed.
490  *
491  * @dev: Device to check
492  * @out_name: Place to put the name (must hold ACPI_NAME_MAX bytes)
493  * @return 0 if a name was found, -ENOENT if not found, -ENXIO if the device
494  *	sequence number could not be determined
495  */
496 int acpi_device_infer_name(const struct udevice *dev, char *out_name);
497 
498 #endif
499