1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Synopsys DesignWare I2C adapter driver.
4  *
5  * Based on the TI DAVINCI I2C adapter driver.
6  *
7  * Copyright (C) 2006 Texas Instruments.
8  * Copyright (C) 2007 MontaVista Software Inc.
9  * Copyright (C) 2009 Provigent Ltd.
10  */
11 
12 #include <linux/bits.h>
13 #include <linux/compiler_types.h>
14 #include <linux/completion.h>
15 #include <linux/dev_printk.h>
16 #include <linux/errno.h>
17 #include <linux/i2c.h>
18 #include <linux/regmap.h>
19 #include <linux/types.h>
20 
21 #define DW_IC_DEFAULT_FUNCTIONALITY		(I2C_FUNC_I2C | \
22 						 I2C_FUNC_SMBUS_BYTE | \
23 						 I2C_FUNC_SMBUS_BYTE_DATA | \
24 						 I2C_FUNC_SMBUS_WORD_DATA | \
25 						 I2C_FUNC_SMBUS_BLOCK_DATA | \
26 						 I2C_FUNC_SMBUS_I2C_BLOCK)
27 
28 #define DW_IC_CON_MASTER			BIT(0)
29 #define DW_IC_CON_SPEED_STD			(1 << 1)
30 #define DW_IC_CON_SPEED_FAST			(2 << 1)
31 #define DW_IC_CON_SPEED_HIGH			(3 << 1)
32 #define DW_IC_CON_SPEED_MASK			GENMASK(2, 1)
33 #define DW_IC_CON_10BITADDR_SLAVE		BIT(3)
34 #define DW_IC_CON_10BITADDR_MASTER		BIT(4)
35 #define DW_IC_CON_RESTART_EN			BIT(5)
36 #define DW_IC_CON_SLAVE_DISABLE			BIT(6)
37 #define DW_IC_CON_STOP_DET_IFADDRESSED		BIT(7)
38 #define DW_IC_CON_TX_EMPTY_CTRL			BIT(8)
39 #define DW_IC_CON_RX_FIFO_FULL_HLD_CTRL		BIT(9)
40 #define DW_IC_CON_BUS_CLEAR_CTRL		BIT(11)
41 
42 #define DW_IC_DATA_CMD_DAT			GENMASK(7, 0)
43 #define DW_IC_DATA_CMD_FIRST_DATA_BYTE		BIT(11)
44 
45 /*
46  * Registers offset
47  */
48 #define DW_IC_CON				0x00
49 #define DW_IC_TAR				0x04
50 #define DW_IC_SAR				0x08
51 #define DW_IC_DATA_CMD				0x10
52 #define DW_IC_SS_SCL_HCNT			0x14
53 #define DW_IC_SS_SCL_LCNT			0x18
54 #define DW_IC_FS_SCL_HCNT			0x1c
55 #define DW_IC_FS_SCL_LCNT			0x20
56 #define DW_IC_HS_SCL_HCNT			0x24
57 #define DW_IC_HS_SCL_LCNT			0x28
58 #define DW_IC_INTR_STAT				0x2c
59 #define DW_IC_INTR_MASK				0x30
60 #define DW_IC_RAW_INTR_STAT			0x34
61 #define DW_IC_RX_TL				0x38
62 #define DW_IC_TX_TL				0x3c
63 #define DW_IC_CLR_INTR				0x40
64 #define DW_IC_CLR_RX_UNDER			0x44
65 #define DW_IC_CLR_RX_OVER			0x48
66 #define DW_IC_CLR_TX_OVER			0x4c
67 #define DW_IC_CLR_RD_REQ			0x50
68 #define DW_IC_CLR_TX_ABRT			0x54
69 #define DW_IC_CLR_RX_DONE			0x58
70 #define DW_IC_CLR_ACTIVITY			0x5c
71 #define DW_IC_CLR_STOP_DET			0x60
72 #define DW_IC_CLR_START_DET			0x64
73 #define DW_IC_CLR_GEN_CALL			0x68
74 #define DW_IC_ENABLE				0x6c
75 #define DW_IC_STATUS				0x70
76 #define DW_IC_TXFLR				0x74
77 #define DW_IC_RXFLR				0x78
78 #define DW_IC_SDA_HOLD				0x7c
79 #define DW_IC_TX_ABRT_SOURCE			0x80
80 #define DW_IC_ENABLE_STATUS			0x9c
81 #define DW_IC_CLR_RESTART_DET			0xa8
82 #define DW_IC_COMP_PARAM_1			0xf4
83 #define DW_IC_COMP_VERSION			0xf8
84 #define DW_IC_SDA_HOLD_MIN_VERS			0x3131312A /* "111*" == v1.11* */
85 #define DW_IC_COMP_TYPE				0xfc
86 #define DW_IC_COMP_TYPE_VALUE			0x44570140 /* "DW" + 0x0140 */
87 
88 #define DW_IC_INTR_RX_UNDER			BIT(0)
89 #define DW_IC_INTR_RX_OVER			BIT(1)
90 #define DW_IC_INTR_RX_FULL			BIT(2)
91 #define DW_IC_INTR_TX_OVER			BIT(3)
92 #define DW_IC_INTR_TX_EMPTY			BIT(4)
93 #define DW_IC_INTR_RD_REQ			BIT(5)
94 #define DW_IC_INTR_TX_ABRT			BIT(6)
95 #define DW_IC_INTR_RX_DONE			BIT(7)
96 #define DW_IC_INTR_ACTIVITY			BIT(8)
97 #define DW_IC_INTR_STOP_DET			BIT(9)
98 #define DW_IC_INTR_START_DET			BIT(10)
99 #define DW_IC_INTR_GEN_CALL			BIT(11)
100 #define DW_IC_INTR_RESTART_DET			BIT(12)
101 
102 #define DW_IC_INTR_DEFAULT_MASK			(DW_IC_INTR_RX_FULL | \
103 						 DW_IC_INTR_TX_ABRT | \
104 						 DW_IC_INTR_STOP_DET)
105 #define DW_IC_INTR_MASTER_MASK			(DW_IC_INTR_DEFAULT_MASK | \
106 						 DW_IC_INTR_TX_EMPTY)
107 #define DW_IC_INTR_SLAVE_MASK			(DW_IC_INTR_DEFAULT_MASK | \
108 						 DW_IC_INTR_RX_UNDER | \
109 						 DW_IC_INTR_RD_REQ)
110 
111 #define DW_IC_STATUS_ACTIVITY			BIT(0)
112 #define DW_IC_STATUS_TFE			BIT(2)
113 #define DW_IC_STATUS_RFNE			BIT(3)
114 #define DW_IC_STATUS_MASTER_ACTIVITY		BIT(5)
115 #define DW_IC_STATUS_SLAVE_ACTIVITY		BIT(6)
116 
117 #define DW_IC_SDA_HOLD_RX_SHIFT			16
118 #define DW_IC_SDA_HOLD_RX_MASK			GENMASK(23, 16)
119 
120 #define DW_IC_ERR_TX_ABRT			0x1
121 
122 #define DW_IC_TAR_10BITADDR_MASTER		BIT(12)
123 
124 #define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH	(BIT(2) | BIT(3))
125 #define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK	GENMASK(3, 2)
126 
127 /*
128  * Sofware status flags
129  */
130 #define STATUS_ACTIVE				BIT(0)
131 #define STATUS_WRITE_IN_PROGRESS		BIT(1)
132 #define STATUS_READ_IN_PROGRESS			BIT(2)
133 #define STATUS_MASK				GENMASK(2, 0)
134 
135 /*
136  * operation modes
137  */
138 #define DW_IC_MASTER				0
139 #define DW_IC_SLAVE				1
140 
141 /*
142  * Hardware abort codes from the DW_IC_TX_ABRT_SOURCE register
143  *
144  * Only expected abort codes are listed here
145  * refer to the datasheet for the full list
146  */
147 #define ABRT_7B_ADDR_NOACK			0
148 #define ABRT_10ADDR1_NOACK			1
149 #define ABRT_10ADDR2_NOACK			2
150 #define ABRT_TXDATA_NOACK			3
151 #define ABRT_GCALL_NOACK			4
152 #define ABRT_GCALL_READ				5
153 #define ABRT_SBYTE_ACKDET			7
154 #define ABRT_SBYTE_NORSTRT			9
155 #define ABRT_10B_RD_NORSTRT			10
156 #define ABRT_MASTER_DIS				11
157 #define ARB_LOST				12
158 #define ABRT_SLAVE_FLUSH_TXFIFO			13
159 #define ABRT_SLAVE_ARBLOST			14
160 #define ABRT_SLAVE_RD_INTX			15
161 
162 #define DW_IC_TX_ABRT_7B_ADDR_NOACK		BIT(ABRT_7B_ADDR_NOACK)
163 #define DW_IC_TX_ABRT_10ADDR1_NOACK		BIT(ABRT_10ADDR1_NOACK)
164 #define DW_IC_TX_ABRT_10ADDR2_NOACK		BIT(ABRT_10ADDR2_NOACK)
165 #define DW_IC_TX_ABRT_TXDATA_NOACK		BIT(ABRT_TXDATA_NOACK)
166 #define DW_IC_TX_ABRT_GCALL_NOACK		BIT(ABRT_GCALL_NOACK)
167 #define DW_IC_TX_ABRT_GCALL_READ		BIT(ABRT_GCALL_READ)
168 #define DW_IC_TX_ABRT_SBYTE_ACKDET		BIT(ABRT_SBYTE_ACKDET)
169 #define DW_IC_TX_ABRT_SBYTE_NORSTRT		BIT(ABRT_SBYTE_NORSTRT)
170 #define DW_IC_TX_ABRT_10B_RD_NORSTRT		BIT(ABRT_10B_RD_NORSTRT)
171 #define DW_IC_TX_ABRT_MASTER_DIS		BIT(ABRT_MASTER_DIS)
172 #define DW_IC_TX_ARB_LOST			BIT(ARB_LOST)
173 #define DW_IC_RX_ABRT_SLAVE_RD_INTX		BIT(ABRT_SLAVE_RD_INTX)
174 #define DW_IC_RX_ABRT_SLAVE_ARBLOST		BIT(ABRT_SLAVE_ARBLOST)
175 #define DW_IC_RX_ABRT_SLAVE_FLUSH_TXFIFO	BIT(ABRT_SLAVE_FLUSH_TXFIFO)
176 
177 #define DW_IC_TX_ABRT_NOACK			(DW_IC_TX_ABRT_7B_ADDR_NOACK | \
178 						 DW_IC_TX_ABRT_10ADDR1_NOACK | \
179 						 DW_IC_TX_ABRT_10ADDR2_NOACK | \
180 						 DW_IC_TX_ABRT_TXDATA_NOACK | \
181 						 DW_IC_TX_ABRT_GCALL_NOACK)
182 
183 struct clk;
184 struct device;
185 struct reset_control;
186 
187 /**
188  * struct dw_i2c_dev - private i2c-designware data
189  * @dev: driver model device node
190  * @map: IO registers map
191  * @sysmap: System controller registers map
192  * @base: IO registers pointer
193  * @ext: Extended IO registers pointer
194  * @cmd_complete: tx completion indicator
195  * @clk: input reference clock
196  * @pclk: clock required to access the registers
197  * @rst: optional reset for the controller
198  * @slave: represent an I2C slave device
199  * @get_clk_rate_khz: callback to retrieve IP specific bus speed
200  * @cmd_err: run time hadware error code
201  * @msgs: points to an array of messages currently being transferred
202  * @msgs_num: the number of elements in msgs
203  * @msg_write_idx: the element index of the current tx message in the msgs array
204  * @tx_buf_len: the length of the current tx buffer
205  * @tx_buf: the current tx buffer
206  * @msg_read_idx: the element index of the current rx message in the msgs array
207  * @rx_buf_len: the length of the current rx buffer
208  * @rx_buf: the current rx buffer
209  * @msg_err: error status of the current transfer
210  * @status: i2c master status, one of STATUS_*
211  * @abort_source: copy of the TX_ABRT_SOURCE register
212  * @irq: interrupt number for the i2c master
213  * @flags: platform specific flags like type of IO accessors or model
214  * @adapter: i2c subsystem adapter node
215  * @functionality: I2C_FUNC_* ORed bits to reflect what controller does support
216  * @master_cfg: configuration for the master device
217  * @slave_cfg: configuration for the slave device
218  * @tx_fifo_depth: depth of the hardware tx fifo
219  * @rx_fifo_depth: depth of the hardware rx fifo
220  * @rx_outstanding: current master-rx elements in tx fifo
221  * @timings: bus clock frequency, SDA hold and other timings
222  * @sda_hold_time: SDA hold value
223  * @ss_hcnt: standard speed HCNT value
224  * @ss_lcnt: standard speed LCNT value
225  * @fs_hcnt: fast speed HCNT value
226  * @fs_lcnt: fast speed LCNT value
227  * @fp_hcnt: fast plus HCNT value
228  * @fp_lcnt: fast plus LCNT value
229  * @hs_hcnt: high speed HCNT value
230  * @hs_lcnt: high speed LCNT value
231  * @acquire_lock: function to acquire a hardware lock on the bus
232  * @release_lock: function to release a hardware lock on the bus
233  * @semaphore_idx: Index of table with semaphore type attached to the bus. It's
234  *	-1 if there is no semaphore.
235  * @shared_with_punit: true if this bus is shared with the SoCs PUNIT
236  * @disable: function to disable the controller
237  * @init: function to initialize the I2C hardware
238  * @set_sda_hold_time: callback to retrieve IP specific SDA hold timing
239  * @mode: operation mode - DW_IC_MASTER or DW_IC_SLAVE
240  * @rinfo: I²C GPIO recovery information
241  *
242  * HCNT and LCNT parameters can be used if the platform knows more accurate
243  * values than the one computed based only on the input clock frequency.
244  * Leave them to be %0 if not used.
245  */
246 struct dw_i2c_dev {
247 	struct device		*dev;
248 	struct regmap		*map;
249 	struct regmap		*sysmap;
250 	void __iomem		*base;
251 	void __iomem		*ext;
252 	struct completion	cmd_complete;
253 	struct clk		*clk;
254 	struct clk		*pclk;
255 	struct reset_control	*rst;
256 	struct i2c_client	*slave;
257 	u32			(*get_clk_rate_khz) (struct dw_i2c_dev *dev);
258 	int			cmd_err;
259 	struct i2c_msg		*msgs;
260 	int			msgs_num;
261 	int			msg_write_idx;
262 	u32			tx_buf_len;
263 	u8			*tx_buf;
264 	int			msg_read_idx;
265 	u32			rx_buf_len;
266 	u8			*rx_buf;
267 	int			msg_err;
268 	unsigned int		status;
269 	unsigned int		abort_source;
270 	int			irq;
271 	u32			flags;
272 	struct i2c_adapter	adapter;
273 	u32			functionality;
274 	u32			master_cfg;
275 	u32			slave_cfg;
276 	unsigned int		tx_fifo_depth;
277 	unsigned int		rx_fifo_depth;
278 	int			rx_outstanding;
279 	struct i2c_timings	timings;
280 	u32			sda_hold_time;
281 	u16			ss_hcnt;
282 	u16			ss_lcnt;
283 	u16			fs_hcnt;
284 	u16			fs_lcnt;
285 	u16			fp_hcnt;
286 	u16			fp_lcnt;
287 	u16			hs_hcnt;
288 	u16			hs_lcnt;
289 	int			(*acquire_lock)(void);
290 	void			(*release_lock)(void);
291 	int			semaphore_idx;
292 	bool			shared_with_punit;
293 	void			(*disable)(struct dw_i2c_dev *dev);
294 	int			(*init)(struct dw_i2c_dev *dev);
295 	int			(*set_sda_hold_time)(struct dw_i2c_dev *dev);
296 	int			mode;
297 	struct i2c_bus_recovery_info rinfo;
298 };
299 
300 #define ACCESS_INTR_MASK			BIT(0)
301 #define ACCESS_NO_IRQ_SUSPEND			BIT(1)
302 #define ARBITRATION_SEMAPHORE			BIT(2)
303 
304 #define MODEL_MSCC_OCELOT			BIT(8)
305 #define MODEL_BAIKAL_BT1			BIT(9)
306 #define MODEL_AMD_NAVI_GPU			BIT(10)
307 #define MODEL_WANGXUN_SP			BIT(11)
308 #define MODEL_MASK				GENMASK(11, 8)
309 
310 /*
311  * Enable UCSI interrupt by writing 0xd at register
312  * offset 0x474 specified in hardware specification.
313  */
314 #define AMD_UCSI_INTR_REG			0x474
315 #define AMD_UCSI_INTR_EN			0xd
316 
317 #define TXGBE_TX_FIFO_DEPTH			4
318 #define TXGBE_RX_FIFO_DEPTH			0
319 
320 struct i2c_dw_semaphore_callbacks {
321 	int	(*probe)(struct dw_i2c_dev *dev);
322 	void	(*remove)(struct dw_i2c_dev *dev);
323 };
324 
325 int i2c_dw_init_regmap(struct dw_i2c_dev *dev);
326 u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset);
327 u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset);
328 int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
329 u32 i2c_dw_clk_rate(struct dw_i2c_dev *dev);
330 int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare);
331 int i2c_dw_acquire_lock(struct dw_i2c_dev *dev);
332 void i2c_dw_release_lock(struct dw_i2c_dev *dev);
333 int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev);
334 int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev);
335 int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev);
336 u32 i2c_dw_func(struct i2c_adapter *adap);
337 void i2c_dw_disable(struct dw_i2c_dev *dev);
338 
339 static inline void __i2c_dw_enable(struct dw_i2c_dev *dev)
340 {
341 	dev->status |= STATUS_ACTIVE;
342 	regmap_write(dev->map, DW_IC_ENABLE, 1);
343 }
344 
345 static inline void __i2c_dw_disable_nowait(struct dw_i2c_dev *dev)
346 {
347 	regmap_write(dev->map, DW_IC_ENABLE, 0);
348 	dev->status &= ~STATUS_ACTIVE;
349 }
350 
351 void __i2c_dw_disable(struct dw_i2c_dev *dev);
352 
353 extern void i2c_dw_configure_master(struct dw_i2c_dev *dev);
354 extern int i2c_dw_probe_master(struct dw_i2c_dev *dev);
355 
356 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_SLAVE)
357 extern void i2c_dw_configure_slave(struct dw_i2c_dev *dev);
358 extern int i2c_dw_probe_slave(struct dw_i2c_dev *dev);
359 #else
360 static inline void i2c_dw_configure_slave(struct dw_i2c_dev *dev) { }
361 static inline int i2c_dw_probe_slave(struct dw_i2c_dev *dev) { return -EINVAL; }
362 #endif
363 
364 static inline int i2c_dw_probe(struct dw_i2c_dev *dev)
365 {
366 	switch (dev->mode) {
367 	case DW_IC_SLAVE:
368 		return i2c_dw_probe_slave(dev);
369 	case DW_IC_MASTER:
370 		return i2c_dw_probe_master(dev);
371 	default:
372 		dev_err(dev->dev, "Wrong operation mode: %d\n", dev->mode);
373 		return -EINVAL;
374 	}
375 }
376 
377 static inline void i2c_dw_configure(struct dw_i2c_dev *dev)
378 {
379 	if (i2c_detect_slave_mode(dev->dev))
380 		i2c_dw_configure_slave(dev);
381 	else
382 		i2c_dw_configure_master(dev);
383 }
384 
385 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL)
386 int i2c_dw_baytrail_probe_lock_support(struct dw_i2c_dev *dev);
387 #endif
388 
389 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_AMDPSP)
390 int i2c_dw_amdpsp_probe_lock_support(struct dw_i2c_dev *dev);
391 #endif
392 
393 int i2c_dw_validate_speed(struct dw_i2c_dev *dev);
394 void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev);
395 
396 #if IS_ENABLED(CONFIG_ACPI)
397 int i2c_dw_acpi_configure(struct device *device);
398 #else
399 static inline int i2c_dw_acpi_configure(struct device *device) { return -ENODEV; }
400 #endif
401