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 
41 #define DW_IC_DATA_CMD_DAT			GENMASK(7, 0)
42 
43 /*
44  * Registers offset
45  */
46 #define DW_IC_CON		0x00
47 #define DW_IC_TAR		0x04
48 #define DW_IC_SAR		0x08
49 #define DW_IC_DATA_CMD		0x10
50 #define DW_IC_SS_SCL_HCNT	0x14
51 #define DW_IC_SS_SCL_LCNT	0x18
52 #define DW_IC_FS_SCL_HCNT	0x1c
53 #define DW_IC_FS_SCL_LCNT	0x20
54 #define DW_IC_HS_SCL_HCNT	0x24
55 #define DW_IC_HS_SCL_LCNT	0x28
56 #define DW_IC_INTR_STAT		0x2c
57 #define DW_IC_INTR_MASK		0x30
58 #define DW_IC_RAW_INTR_STAT	0x34
59 #define DW_IC_RX_TL		0x38
60 #define DW_IC_TX_TL		0x3c
61 #define DW_IC_CLR_INTR		0x40
62 #define DW_IC_CLR_RX_UNDER	0x44
63 #define DW_IC_CLR_RX_OVER	0x48
64 #define DW_IC_CLR_TX_OVER	0x4c
65 #define DW_IC_CLR_RD_REQ	0x50
66 #define DW_IC_CLR_TX_ABRT	0x54
67 #define DW_IC_CLR_RX_DONE	0x58
68 #define DW_IC_CLR_ACTIVITY	0x5c
69 #define DW_IC_CLR_STOP_DET	0x60
70 #define DW_IC_CLR_START_DET	0x64
71 #define DW_IC_CLR_GEN_CALL	0x68
72 #define DW_IC_ENABLE		0x6c
73 #define DW_IC_STATUS		0x70
74 #define DW_IC_TXFLR		0x74
75 #define DW_IC_RXFLR		0x78
76 #define DW_IC_SDA_HOLD		0x7c
77 #define DW_IC_TX_ABRT_SOURCE	0x80
78 #define DW_IC_ENABLE_STATUS	0x9c
79 #define DW_IC_CLR_RESTART_DET	0xa8
80 #define DW_IC_COMP_PARAM_1	0xf4
81 #define DW_IC_COMP_VERSION	0xf8
82 #define DW_IC_SDA_HOLD_MIN_VERS	0x3131312A
83 #define DW_IC_COMP_TYPE		0xfc
84 #define DW_IC_COMP_TYPE_VALUE	0x44570140
85 
86 #define DW_IC_INTR_RX_UNDER	BIT(0)
87 #define DW_IC_INTR_RX_OVER	BIT(1)
88 #define DW_IC_INTR_RX_FULL	BIT(2)
89 #define DW_IC_INTR_TX_OVER	BIT(3)
90 #define DW_IC_INTR_TX_EMPTY	BIT(4)
91 #define DW_IC_INTR_RD_REQ	BIT(5)
92 #define DW_IC_INTR_TX_ABRT	BIT(6)
93 #define DW_IC_INTR_RX_DONE	BIT(7)
94 #define DW_IC_INTR_ACTIVITY	BIT(8)
95 #define DW_IC_INTR_STOP_DET	BIT(9)
96 #define DW_IC_INTR_START_DET	BIT(10)
97 #define DW_IC_INTR_GEN_CALL	BIT(11)
98 #define DW_IC_INTR_RESTART_DET	BIT(12)
99 
100 #define DW_IC_INTR_DEFAULT_MASK		(DW_IC_INTR_RX_FULL | \
101 					 DW_IC_INTR_TX_ABRT | \
102 					 DW_IC_INTR_STOP_DET)
103 #define DW_IC_INTR_MASTER_MASK		(DW_IC_INTR_DEFAULT_MASK | \
104 					 DW_IC_INTR_TX_EMPTY)
105 #define DW_IC_INTR_SLAVE_MASK		(DW_IC_INTR_DEFAULT_MASK | \
106 					 DW_IC_INTR_RX_DONE | \
107 					 DW_IC_INTR_RX_UNDER | \
108 					 DW_IC_INTR_RD_REQ)
109 
110 #define DW_IC_STATUS_ACTIVITY		BIT(0)
111 #define DW_IC_STATUS_TFE		BIT(2)
112 #define DW_IC_STATUS_MASTER_ACTIVITY	BIT(5)
113 #define DW_IC_STATUS_SLAVE_ACTIVITY	BIT(6)
114 
115 #define DW_IC_SDA_HOLD_RX_SHIFT		16
116 #define DW_IC_SDA_HOLD_RX_MASK		GENMASK(23, 16)
117 
118 #define DW_IC_ERR_TX_ABRT	0x1
119 
120 #define DW_IC_TAR_10BITADDR_MASTER	BIT(12)
121 
122 #define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH	(BIT(2) | BIT(3))
123 #define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK	GENMASK(3, 2)
124 
125 /*
126  * status codes
127  */
128 #define STATUS_IDLE			0x0
129 #define STATUS_WRITE_IN_PROGRESS	0x1
130 #define STATUS_READ_IN_PROGRESS		0x2
131 
132 /*
133  * operation modes
134  */
135 #define DW_IC_MASTER		0
136 #define DW_IC_SLAVE		1
137 
138 /*
139  * Hardware abort codes from the DW_IC_TX_ABRT_SOURCE register
140  *
141  * Only expected abort codes are listed here
142  * refer to the datasheet for the full list
143  */
144 #define ABRT_7B_ADDR_NOACK	0
145 #define ABRT_10ADDR1_NOACK	1
146 #define ABRT_10ADDR2_NOACK	2
147 #define ABRT_TXDATA_NOACK	3
148 #define ABRT_GCALL_NOACK	4
149 #define ABRT_GCALL_READ		5
150 #define ABRT_SBYTE_ACKDET	7
151 #define ABRT_SBYTE_NORSTRT	9
152 #define ABRT_10B_RD_NORSTRT	10
153 #define ABRT_MASTER_DIS		11
154 #define ARB_LOST		12
155 #define ABRT_SLAVE_FLUSH_TXFIFO	13
156 #define ABRT_SLAVE_ARBLOST	14
157 #define ABRT_SLAVE_RD_INTX	15
158 
159 #define DW_IC_TX_ABRT_7B_ADDR_NOACK		BIT(ABRT_7B_ADDR_NOACK)
160 #define DW_IC_TX_ABRT_10ADDR1_NOACK		BIT(ABRT_10ADDR1_NOACK)
161 #define DW_IC_TX_ABRT_10ADDR2_NOACK		BIT(ABRT_10ADDR2_NOACK)
162 #define DW_IC_TX_ABRT_TXDATA_NOACK		BIT(ABRT_TXDATA_NOACK)
163 #define DW_IC_TX_ABRT_GCALL_NOACK		BIT(ABRT_GCALL_NOACK)
164 #define DW_IC_TX_ABRT_GCALL_READ		BIT(ABRT_GCALL_READ)
165 #define DW_IC_TX_ABRT_SBYTE_ACKDET		BIT(ABRT_SBYTE_ACKDET)
166 #define DW_IC_TX_ABRT_SBYTE_NORSTRT		BIT(ABRT_SBYTE_NORSTRT)
167 #define DW_IC_TX_ABRT_10B_RD_NORSTRT		BIT(ABRT_10B_RD_NORSTRT)
168 #define DW_IC_TX_ABRT_MASTER_DIS		BIT(ABRT_MASTER_DIS)
169 #define DW_IC_TX_ARB_LOST			BIT(ARB_LOST)
170 #define DW_IC_RX_ABRT_SLAVE_RD_INTX		BIT(ABRT_SLAVE_RD_INTX)
171 #define DW_IC_RX_ABRT_SLAVE_ARBLOST		BIT(ABRT_SLAVE_ARBLOST)
172 #define DW_IC_RX_ABRT_SLAVE_FLUSH_TXFIFO	BIT(ABRT_SLAVE_FLUSH_TXFIFO)
173 
174 #define DW_IC_TX_ABRT_NOACK		(DW_IC_TX_ABRT_7B_ADDR_NOACK | \
175 					 DW_IC_TX_ABRT_10ADDR1_NOACK | \
176 					 DW_IC_TX_ABRT_10ADDR2_NOACK | \
177 					 DW_IC_TX_ABRT_TXDATA_NOACK | \
178 					 DW_IC_TX_ABRT_GCALL_NOACK)
179 
180 struct clk;
181 struct device;
182 struct reset_control;
183 
184 /**
185  * struct dw_i2c_dev - private i2c-designware data
186  * @dev: driver model device node
187  * @map: IO registers map
188  * @sysmap: System controller registers map
189  * @base: IO registers pointer
190  * @ext: Extended IO registers pointer
191  * @cmd_complete: tx completion indicator
192  * @clk: input reference clock
193  * @pclk: clock required to access the registers
194  * @slave: represent an I2C slave device
195  * @cmd_err: run time hadware error code
196  * @msgs: points to an array of messages currently being transferred
197  * @msgs_num: the number of elements in msgs
198  * @msg_write_idx: the element index of the current tx message in the msgs
199  *	array
200  * @tx_buf_len: the length of the current tx buffer
201  * @tx_buf: the current tx buffer
202  * @msg_read_idx: the element index of the current rx message in the msgs
203  *	array
204  * @rx_buf_len: the length of the current rx buffer
205  * @rx_buf: the current rx buffer
206  * @msg_err: error status of the current transfer
207  * @status: i2c master status, one of STATUS_*
208  * @abort_source: copy of the TX_ABRT_SOURCE register
209  * @irq: interrupt number for the i2c master
210  * @adapter: i2c subsystem adapter node
211  * @slave_cfg: configuration for the slave device
212  * @tx_fifo_depth: depth of the hardware tx fifo
213  * @rx_fifo_depth: depth of the hardware rx fifo
214  * @rx_outstanding: current master-rx elements in tx fifo
215  * @timings: bus clock frequency, SDA hold and other timings
216  * @sda_hold_time: SDA hold value
217  * @ss_hcnt: standard speed HCNT value
218  * @ss_lcnt: standard speed LCNT value
219  * @fs_hcnt: fast speed HCNT value
220  * @fs_lcnt: fast speed LCNT value
221  * @fp_hcnt: fast plus HCNT value
222  * @fp_lcnt: fast plus LCNT value
223  * @hs_hcnt: high speed HCNT value
224  * @hs_lcnt: high speed LCNT value
225  * @acquire_lock: function to acquire a hardware lock on the bus
226  * @release_lock: function to release a hardware lock on the bus
227  * @shared_with_punit: true if this bus is shared with the SoCs PUNIT
228  * @disable: function to disable the controller
229  * @disable_int: function to disable all interrupts
230  * @init: function to initialize the I2C hardware
231  * @mode: operation mode - DW_IC_MASTER or DW_IC_SLAVE
232  * @suspended: set to true if the controller is suspended
233  *
234  * HCNT and LCNT parameters can be used if the platform knows more accurate
235  * values than the one computed based only on the input clock frequency.
236  * Leave them to be %0 if not used.
237  */
238 struct dw_i2c_dev {
239 	struct device		*dev;
240 	struct regmap		*map;
241 	struct regmap		*sysmap;
242 	void __iomem		*base;
243 	void __iomem		*ext;
244 	struct completion	cmd_complete;
245 	struct clk		*clk;
246 	struct clk		*pclk;
247 	struct reset_control	*rst;
248 	struct i2c_client	*slave;
249 	u32			(*get_clk_rate_khz) (struct dw_i2c_dev *dev);
250 	int			cmd_err;
251 	struct i2c_msg		*msgs;
252 	int			msgs_num;
253 	int			msg_write_idx;
254 	u32			tx_buf_len;
255 	u8			*tx_buf;
256 	int			msg_read_idx;
257 	u32			rx_buf_len;
258 	u8			*rx_buf;
259 	int			msg_err;
260 	unsigned int		status;
261 	u32			abort_source;
262 	int			irq;
263 	u32			flags;
264 	struct i2c_adapter	adapter;
265 	u32			functionality;
266 	u32			master_cfg;
267 	u32			slave_cfg;
268 	unsigned int		tx_fifo_depth;
269 	unsigned int		rx_fifo_depth;
270 	int			rx_outstanding;
271 	struct i2c_timings	timings;
272 	u32			sda_hold_time;
273 	u16			ss_hcnt;
274 	u16			ss_lcnt;
275 	u16			fs_hcnt;
276 	u16			fs_lcnt;
277 	u16			fp_hcnt;
278 	u16			fp_lcnt;
279 	u16			hs_hcnt;
280 	u16			hs_lcnt;
281 	int			(*acquire_lock)(void);
282 	void			(*release_lock)(void);
283 	bool			shared_with_punit;
284 	void			(*disable)(struct dw_i2c_dev *dev);
285 	void			(*disable_int)(struct dw_i2c_dev *dev);
286 	int			(*init)(struct dw_i2c_dev *dev);
287 	int			(*set_sda_hold_time)(struct dw_i2c_dev *dev);
288 	int			mode;
289 	struct i2c_bus_recovery_info rinfo;
290 	bool			suspended;
291 };
292 
293 #define ACCESS_INTR_MASK	BIT(0)
294 #define ACCESS_NO_IRQ_SUSPEND	BIT(1)
295 
296 #define MODEL_MSCC_OCELOT	BIT(8)
297 #define MODEL_BAIKAL_BT1	BIT(9)
298 #define MODEL_AMD_NAVI_GPU	BIT(10)
299 #define MODEL_MASK		GENMASK(11, 8)
300 
301 /*
302  * Enable UCSI interrupt by writing 0xd at register
303  * offset 0x474 specified in hardware specification.
304  */
305 #define AMD_UCSI_INTR_REG	0x474
306 #define AMD_UCSI_INTR_EN	0xd
307 
308 int i2c_dw_init_regmap(struct dw_i2c_dev *dev);
309 u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset);
310 u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset);
311 int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
312 unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev);
313 int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare);
314 int i2c_dw_acquire_lock(struct dw_i2c_dev *dev);
315 void i2c_dw_release_lock(struct dw_i2c_dev *dev);
316 int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev);
317 int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev);
318 int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev);
319 u32 i2c_dw_func(struct i2c_adapter *adap);
320 void i2c_dw_disable(struct dw_i2c_dev *dev);
321 void i2c_dw_disable_int(struct dw_i2c_dev *dev);
322 
323 static inline void __i2c_dw_enable(struct dw_i2c_dev *dev)
324 {
325 	regmap_write(dev->map, DW_IC_ENABLE, 1);
326 }
327 
328 static inline void __i2c_dw_disable_nowait(struct dw_i2c_dev *dev)
329 {
330 	regmap_write(dev->map, DW_IC_ENABLE, 0);
331 }
332 
333 void __i2c_dw_disable(struct dw_i2c_dev *dev);
334 
335 extern void i2c_dw_configure_master(struct dw_i2c_dev *dev);
336 extern int i2c_dw_probe_master(struct dw_i2c_dev *dev);
337 
338 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_SLAVE)
339 extern void i2c_dw_configure_slave(struct dw_i2c_dev *dev);
340 extern int i2c_dw_probe_slave(struct dw_i2c_dev *dev);
341 #else
342 static inline void i2c_dw_configure_slave(struct dw_i2c_dev *dev) { }
343 static inline int i2c_dw_probe_slave(struct dw_i2c_dev *dev) { return -EINVAL; }
344 #endif
345 
346 static inline int i2c_dw_probe(struct dw_i2c_dev *dev)
347 {
348 	switch (dev->mode) {
349 	case DW_IC_SLAVE:
350 		return i2c_dw_probe_slave(dev);
351 	case DW_IC_MASTER:
352 		return i2c_dw_probe_master(dev);
353 	default:
354 		dev_err(dev->dev, "Wrong operation mode: %d\n", dev->mode);
355 		return -EINVAL;
356 	}
357 }
358 
359 static inline void i2c_dw_configure(struct dw_i2c_dev *dev)
360 {
361 	if (i2c_detect_slave_mode(dev->dev))
362 		i2c_dw_configure_slave(dev);
363 	else
364 		i2c_dw_configure_master(dev);
365 }
366 
367 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL)
368 extern int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev);
369 #else
370 static inline int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) { return 0; }
371 #endif
372 
373 int i2c_dw_validate_speed(struct dw_i2c_dev *dev);
374 void i2c_dw_adjust_bus_speed(struct dw_i2c_dev *dev);
375 
376 #if IS_ENABLED(CONFIG_ACPI)
377 int i2c_dw_acpi_configure(struct device *device);
378 #else
379 static inline int i2c_dw_acpi_configure(struct device *device) { return -ENODEV; }
380 #endif
381