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		0x1
29 #define DW_IC_CON_SPEED_STD		0x2
30 #define DW_IC_CON_SPEED_FAST		0x4
31 #define DW_IC_CON_SPEED_HIGH		0x6
32 #define DW_IC_CON_SPEED_MASK		0x6
33 #define DW_IC_CON_10BITADDR_SLAVE		0x8
34 #define DW_IC_CON_10BITADDR_MASTER	0x10
35 #define DW_IC_CON_RESTART_EN		0x20
36 #define DW_IC_CON_SLAVE_DISABLE		0x40
37 #define DW_IC_CON_STOP_DET_IFADDRESSED		0x80
38 #define DW_IC_CON_TX_EMPTY_CTRL		0x100
39 #define DW_IC_CON_RX_FIFO_FULL_HLD_CTRL		0x200
40 
41 /*
42  * Registers offset
43  */
44 #define DW_IC_CON		0x0
45 #define DW_IC_TAR		0x4
46 #define DW_IC_SAR		0x8
47 #define DW_IC_DATA_CMD		0x10
48 #define DW_IC_SS_SCL_HCNT	0x14
49 #define DW_IC_SS_SCL_LCNT	0x18
50 #define DW_IC_FS_SCL_HCNT	0x1c
51 #define DW_IC_FS_SCL_LCNT	0x20
52 #define DW_IC_HS_SCL_HCNT	0x24
53 #define DW_IC_HS_SCL_LCNT	0x28
54 #define DW_IC_INTR_STAT		0x2c
55 #define DW_IC_INTR_MASK		0x30
56 #define DW_IC_RAW_INTR_STAT	0x34
57 #define DW_IC_RX_TL		0x38
58 #define DW_IC_TX_TL		0x3c
59 #define DW_IC_CLR_INTR		0x40
60 #define DW_IC_CLR_RX_UNDER	0x44
61 #define DW_IC_CLR_RX_OVER	0x48
62 #define DW_IC_CLR_TX_OVER	0x4c
63 #define DW_IC_CLR_RD_REQ	0x50
64 #define DW_IC_CLR_TX_ABRT	0x54
65 #define DW_IC_CLR_RX_DONE	0x58
66 #define DW_IC_CLR_ACTIVITY	0x5c
67 #define DW_IC_CLR_STOP_DET	0x60
68 #define DW_IC_CLR_START_DET	0x64
69 #define DW_IC_CLR_GEN_CALL	0x68
70 #define DW_IC_ENABLE		0x6c
71 #define DW_IC_STATUS		0x70
72 #define DW_IC_TXFLR		0x74
73 #define DW_IC_RXFLR		0x78
74 #define DW_IC_SDA_HOLD		0x7c
75 #define DW_IC_TX_ABRT_SOURCE	0x80
76 #define DW_IC_ENABLE_STATUS	0x9c
77 #define DW_IC_CLR_RESTART_DET	0xa8
78 #define DW_IC_COMP_PARAM_1	0xf4
79 #define DW_IC_COMP_VERSION	0xf8
80 #define DW_IC_SDA_HOLD_MIN_VERS	0x3131312A
81 #define DW_IC_COMP_TYPE		0xfc
82 #define DW_IC_COMP_TYPE_VALUE	0x44570140
83 
84 #define DW_IC_INTR_RX_UNDER	0x001
85 #define DW_IC_INTR_RX_OVER	0x002
86 #define DW_IC_INTR_RX_FULL	0x004
87 #define DW_IC_INTR_TX_OVER	0x008
88 #define DW_IC_INTR_TX_EMPTY	0x010
89 #define DW_IC_INTR_RD_REQ	0x020
90 #define DW_IC_INTR_TX_ABRT	0x040
91 #define DW_IC_INTR_RX_DONE	0x080
92 #define DW_IC_INTR_ACTIVITY	0x100
93 #define DW_IC_INTR_STOP_DET	0x200
94 #define DW_IC_INTR_START_DET	0x400
95 #define DW_IC_INTR_GEN_CALL	0x800
96 #define DW_IC_INTR_RESTART_DET	0x1000
97 
98 #define DW_IC_INTR_DEFAULT_MASK		(DW_IC_INTR_RX_FULL | \
99 					 DW_IC_INTR_TX_ABRT | \
100 					 DW_IC_INTR_STOP_DET)
101 #define DW_IC_INTR_MASTER_MASK		(DW_IC_INTR_DEFAULT_MASK | \
102 					 DW_IC_INTR_TX_EMPTY)
103 #define DW_IC_INTR_SLAVE_MASK		(DW_IC_INTR_DEFAULT_MASK | \
104 					 DW_IC_INTR_RX_DONE | \
105 					 DW_IC_INTR_RX_UNDER | \
106 					 DW_IC_INTR_RD_REQ)
107 
108 #define DW_IC_STATUS_ACTIVITY		0x1
109 #define DW_IC_STATUS_TFE		BIT(2)
110 #define DW_IC_STATUS_MASTER_ACTIVITY	BIT(5)
111 #define DW_IC_STATUS_SLAVE_ACTIVITY	BIT(6)
112 
113 #define DW_IC_SDA_HOLD_RX_SHIFT		16
114 #define DW_IC_SDA_HOLD_RX_MASK		GENMASK(23, DW_IC_SDA_HOLD_RX_SHIFT)
115 
116 #define DW_IC_ERR_TX_ABRT	0x1
117 
118 #define DW_IC_TAR_10BITADDR_MASTER BIT(12)
119 
120 #define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH	(BIT(2) | BIT(3))
121 #define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK	GENMASK(3, 2)
122 
123 /*
124  * status codes
125  */
126 #define STATUS_IDLE			0x0
127 #define STATUS_WRITE_IN_PROGRESS	0x1
128 #define STATUS_READ_IN_PROGRESS		0x2
129 
130 /*
131  * operation modes
132  */
133 #define DW_IC_MASTER		0
134 #define DW_IC_SLAVE		1
135 
136 /*
137  * Hardware abort codes from the DW_IC_TX_ABRT_SOURCE register
138  *
139  * Only expected abort codes are listed here
140  * refer to the datasheet for the full list
141  */
142 #define ABRT_7B_ADDR_NOACK	0
143 #define ABRT_10ADDR1_NOACK	1
144 #define ABRT_10ADDR2_NOACK	2
145 #define ABRT_TXDATA_NOACK	3
146 #define ABRT_GCALL_NOACK	4
147 #define ABRT_GCALL_READ		5
148 #define ABRT_SBYTE_ACKDET	7
149 #define ABRT_SBYTE_NORSTRT	9
150 #define ABRT_10B_RD_NORSTRT	10
151 #define ABRT_MASTER_DIS		11
152 #define ARB_LOST		12
153 #define ABRT_SLAVE_FLUSH_TXFIFO	13
154 #define ABRT_SLAVE_ARBLOST	14
155 #define ABRT_SLAVE_RD_INTX	15
156 
157 #define DW_IC_TX_ABRT_7B_ADDR_NOACK	(1UL << ABRT_7B_ADDR_NOACK)
158 #define DW_IC_TX_ABRT_10ADDR1_NOACK	(1UL << ABRT_10ADDR1_NOACK)
159 #define DW_IC_TX_ABRT_10ADDR2_NOACK	(1UL << ABRT_10ADDR2_NOACK)
160 #define DW_IC_TX_ABRT_TXDATA_NOACK	(1UL << ABRT_TXDATA_NOACK)
161 #define DW_IC_TX_ABRT_GCALL_NOACK	(1UL << ABRT_GCALL_NOACK)
162 #define DW_IC_TX_ABRT_GCALL_READ	(1UL << ABRT_GCALL_READ)
163 #define DW_IC_TX_ABRT_SBYTE_ACKDET	(1UL << ABRT_SBYTE_ACKDET)
164 #define DW_IC_TX_ABRT_SBYTE_NORSTRT	(1UL << ABRT_SBYTE_NORSTRT)
165 #define DW_IC_TX_ABRT_10B_RD_NORSTRT	(1UL << ABRT_10B_RD_NORSTRT)
166 #define DW_IC_TX_ABRT_MASTER_DIS	(1UL << ABRT_MASTER_DIS)
167 #define DW_IC_TX_ARB_LOST		(1UL << ARB_LOST)
168 #define DW_IC_RX_ABRT_SLAVE_RD_INTX	(1UL << ABRT_SLAVE_RD_INTX)
169 #define DW_IC_RX_ABRT_SLAVE_ARBLOST	(1UL << ABRT_SLAVE_ARBLOST)
170 #define DW_IC_RX_ABRT_SLAVE_FLUSH_TXFIFO	(1UL << ABRT_SLAVE_FLUSH_TXFIFO)
171 
172 #define DW_IC_TX_ABRT_NOACK		(DW_IC_TX_ABRT_7B_ADDR_NOACK | \
173 					 DW_IC_TX_ABRT_10ADDR1_NOACK | \
174 					 DW_IC_TX_ABRT_10ADDR2_NOACK | \
175 					 DW_IC_TX_ABRT_TXDATA_NOACK | \
176 					 DW_IC_TX_ABRT_GCALL_NOACK)
177 
178 struct clk;
179 struct device;
180 struct reset_control;
181 
182 /**
183  * struct dw_i2c_dev - private i2c-designware data
184  * @dev: driver model device node
185  * @map: IO registers map
186  * @sysmap: System controller registers map
187  * @base: IO registers pointer
188  * @ext: Extended IO registers pointer
189  * @cmd_complete: tx completion indicator
190  * @clk: input reference clock
191  * @pclk: clock required to access the registers
192  * @slave: represent an I2C slave device
193  * @cmd_err: run time hadware error code
194  * @msgs: points to an array of messages currently being transferred
195  * @msgs_num: the number of elements in msgs
196  * @msg_write_idx: the element index of the current tx message in the msgs
197  *	array
198  * @tx_buf_len: the length of the current tx buffer
199  * @tx_buf: the current tx buffer
200  * @msg_read_idx: the element index of the current rx message in the msgs
201  *	array
202  * @rx_buf_len: the length of the current rx buffer
203  * @rx_buf: the current rx buffer
204  * @msg_err: error status of the current transfer
205  * @status: i2c master status, one of STATUS_*
206  * @abort_source: copy of the TX_ABRT_SOURCE register
207  * @irq: interrupt number for the i2c master
208  * @adapter: i2c subsystem adapter node
209  * @slave_cfg: configuration for the slave device
210  * @tx_fifo_depth: depth of the hardware tx fifo
211  * @rx_fifo_depth: depth of the hardware rx fifo
212  * @rx_outstanding: current master-rx elements in tx fifo
213  * @timings: bus clock frequency, SDA hold and other timings
214  * @sda_hold_time: SDA hold value
215  * @ss_hcnt: standard speed HCNT value
216  * @ss_lcnt: standard speed LCNT value
217  * @fs_hcnt: fast speed HCNT value
218  * @fs_lcnt: fast speed LCNT value
219  * @fp_hcnt: fast plus HCNT value
220  * @fp_lcnt: fast plus LCNT value
221  * @hs_hcnt: high speed HCNT value
222  * @hs_lcnt: high speed LCNT value
223  * @acquire_lock: function to acquire a hardware lock on the bus
224  * @release_lock: function to release a hardware lock on the bus
225  * @shared_with_punit: true if this bus is shared with the SoCs PUNIT
226  * @disable: function to disable the controller
227  * @disable_int: function to disable all interrupts
228  * @init: function to initialize the I2C hardware
229  * @mode: operation mode - DW_IC_MASTER or DW_IC_SLAVE
230  * @suspended: set to true if the controller is suspended
231  *
232  * HCNT and LCNT parameters can be used if the platform knows more accurate
233  * values than the one computed based only on the input clock frequency.
234  * Leave them to be %0 if not used.
235  */
236 struct dw_i2c_dev {
237 	struct device		*dev;
238 	struct regmap		*map;
239 	struct regmap		*sysmap;
240 	void __iomem		*base;
241 	void __iomem		*ext;
242 	struct completion	cmd_complete;
243 	struct clk		*clk;
244 	struct clk		*pclk;
245 	struct reset_control	*rst;
246 	struct i2c_client		*slave;
247 	u32			(*get_clk_rate_khz) (struct dw_i2c_dev *dev);
248 	int			cmd_err;
249 	struct i2c_msg		*msgs;
250 	int			msgs_num;
251 	int			msg_write_idx;
252 	u32			tx_buf_len;
253 	u8			*tx_buf;
254 	int			msg_read_idx;
255 	u32			rx_buf_len;
256 	u8			*rx_buf;
257 	int			msg_err;
258 	unsigned int		status;
259 	u32			abort_source;
260 	int			irq;
261 	u32			flags;
262 	struct i2c_adapter	adapter;
263 	u32			functionality;
264 	u32			master_cfg;
265 	u32			slave_cfg;
266 	unsigned int		tx_fifo_depth;
267 	unsigned int		rx_fifo_depth;
268 	int			rx_outstanding;
269 	struct i2c_timings	timings;
270 	u32			sda_hold_time;
271 	u16			ss_hcnt;
272 	u16			ss_lcnt;
273 	u16			fs_hcnt;
274 	u16			fs_lcnt;
275 	u16			fp_hcnt;
276 	u16			fp_lcnt;
277 	u16			hs_hcnt;
278 	u16			hs_lcnt;
279 	int			(*acquire_lock)(void);
280 	void			(*release_lock)(void);
281 	bool			shared_with_punit;
282 	void			(*disable)(struct dw_i2c_dev *dev);
283 	void			(*disable_int)(struct dw_i2c_dev *dev);
284 	int			(*init)(struct dw_i2c_dev *dev);
285 	int			(*set_sda_hold_time)(struct dw_i2c_dev *dev);
286 	int			mode;
287 	struct i2c_bus_recovery_info rinfo;
288 	bool			suspended;
289 };
290 
291 #define ACCESS_INTR_MASK	0x00000001
292 #define ACCESS_NO_IRQ_SUSPEND	0x00000002
293 
294 #define MODEL_MSCC_OCELOT	0x00000100
295 #define MODEL_BAIKAL_BT1	0x00000200
296 #define MODEL_MASK		0x00000f00
297 
298 int i2c_dw_init_regmap(struct dw_i2c_dev *dev);
299 u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset);
300 u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset);
301 int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
302 unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev);
303 int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare);
304 int i2c_dw_acquire_lock(struct dw_i2c_dev *dev);
305 void i2c_dw_release_lock(struct dw_i2c_dev *dev);
306 int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev);
307 int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev);
308 int i2c_dw_set_fifo_size(struct dw_i2c_dev *dev);
309 u32 i2c_dw_func(struct i2c_adapter *adap);
310 void i2c_dw_disable(struct dw_i2c_dev *dev);
311 void i2c_dw_disable_int(struct dw_i2c_dev *dev);
312 
313 static inline void __i2c_dw_enable(struct dw_i2c_dev *dev)
314 {
315 	regmap_write(dev->map, DW_IC_ENABLE, 1);
316 }
317 
318 static inline void __i2c_dw_disable_nowait(struct dw_i2c_dev *dev)
319 {
320 	regmap_write(dev->map, DW_IC_ENABLE, 0);
321 }
322 
323 void __i2c_dw_disable(struct dw_i2c_dev *dev);
324 
325 extern void i2c_dw_configure_master(struct dw_i2c_dev *dev);
326 extern int i2c_dw_probe_master(struct dw_i2c_dev *dev);
327 
328 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_SLAVE)
329 extern void i2c_dw_configure_slave(struct dw_i2c_dev *dev);
330 extern int i2c_dw_probe_slave(struct dw_i2c_dev *dev);
331 #else
332 static inline void i2c_dw_configure_slave(struct dw_i2c_dev *dev) { }
333 static inline int i2c_dw_probe_slave(struct dw_i2c_dev *dev) { return -EINVAL; }
334 #endif
335 
336 static inline int i2c_dw_probe(struct dw_i2c_dev *dev)
337 {
338 	switch (dev->mode) {
339 	case DW_IC_SLAVE:
340 		return i2c_dw_probe_slave(dev);
341 	case DW_IC_MASTER:
342 		return i2c_dw_probe_master(dev);
343 	default:
344 		dev_err(dev->dev, "Wrong operation mode: %d\n", dev->mode);
345 		return -EINVAL;
346 	}
347 }
348 
349 static inline void i2c_dw_configure(struct dw_i2c_dev *dev)
350 {
351 	if (i2c_detect_slave_mode(dev->dev))
352 		i2c_dw_configure_slave(dev);
353 	else
354 		i2c_dw_configure_master(dev);
355 }
356 
357 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL)
358 extern int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev);
359 #else
360 static inline int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) { return 0; }
361 #endif
362 
363 int i2c_dw_validate_speed(struct dw_i2c_dev *dev);
364 
365 #if IS_ENABLED(CONFIG_ACPI)
366 int i2c_dw_acpi_configure(struct device *device);
367 void i2c_dw_acpi_adjust_bus_speed(struct device *device);
368 #else
369 static inline int i2c_dw_acpi_configure(struct device *device) { return -ENODEV; }
370 static inline void i2c_dw_acpi_adjust_bus_speed(struct device *device) {}
371 #endif
372