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/i2c.h>
13 
14 #define DW_IC_DEFAULT_FUNCTIONALITY (I2C_FUNC_I2C |			\
15 					I2C_FUNC_SMBUS_BYTE |		\
16 					I2C_FUNC_SMBUS_BYTE_DATA |	\
17 					I2C_FUNC_SMBUS_WORD_DATA |	\
18 					I2C_FUNC_SMBUS_BLOCK_DATA |	\
19 					I2C_FUNC_SMBUS_I2C_BLOCK)
20 
21 #define DW_IC_CON_MASTER		0x1
22 #define DW_IC_CON_SPEED_STD		0x2
23 #define DW_IC_CON_SPEED_FAST		0x4
24 #define DW_IC_CON_SPEED_HIGH		0x6
25 #define DW_IC_CON_SPEED_MASK		0x6
26 #define DW_IC_CON_10BITADDR_SLAVE		0x8
27 #define DW_IC_CON_10BITADDR_MASTER	0x10
28 #define DW_IC_CON_RESTART_EN		0x20
29 #define DW_IC_CON_SLAVE_DISABLE		0x40
30 #define DW_IC_CON_STOP_DET_IFADDRESSED		0x80
31 #define DW_IC_CON_TX_EMPTY_CTRL		0x100
32 #define DW_IC_CON_RX_FIFO_FULL_HLD_CTRL		0x200
33 
34 /*
35  * Registers offset
36  */
37 #define DW_IC_CON		0x0
38 #define DW_IC_TAR		0x4
39 #define DW_IC_SAR		0x8
40 #define DW_IC_DATA_CMD		0x10
41 #define DW_IC_SS_SCL_HCNT	0x14
42 #define DW_IC_SS_SCL_LCNT	0x18
43 #define DW_IC_FS_SCL_HCNT	0x1c
44 #define DW_IC_FS_SCL_LCNT	0x20
45 #define DW_IC_HS_SCL_HCNT	0x24
46 #define DW_IC_HS_SCL_LCNT	0x28
47 #define DW_IC_INTR_STAT		0x2c
48 #define DW_IC_INTR_MASK		0x30
49 #define DW_IC_RAW_INTR_STAT	0x34
50 #define DW_IC_RX_TL		0x38
51 #define DW_IC_TX_TL		0x3c
52 #define DW_IC_CLR_INTR		0x40
53 #define DW_IC_CLR_RX_UNDER	0x44
54 #define DW_IC_CLR_RX_OVER	0x48
55 #define DW_IC_CLR_TX_OVER	0x4c
56 #define DW_IC_CLR_RD_REQ	0x50
57 #define DW_IC_CLR_TX_ABRT	0x54
58 #define DW_IC_CLR_RX_DONE	0x58
59 #define DW_IC_CLR_ACTIVITY	0x5c
60 #define DW_IC_CLR_STOP_DET	0x60
61 #define DW_IC_CLR_START_DET	0x64
62 #define DW_IC_CLR_GEN_CALL	0x68
63 #define DW_IC_ENABLE		0x6c
64 #define DW_IC_STATUS		0x70
65 #define DW_IC_TXFLR		0x74
66 #define DW_IC_RXFLR		0x78
67 #define DW_IC_SDA_HOLD		0x7c
68 #define DW_IC_TX_ABRT_SOURCE	0x80
69 #define DW_IC_ENABLE_STATUS	0x9c
70 #define DW_IC_CLR_RESTART_DET	0xa8
71 #define DW_IC_COMP_PARAM_1	0xf4
72 #define DW_IC_COMP_VERSION	0xf8
73 #define DW_IC_SDA_HOLD_MIN_VERS	0x3131312A
74 #define DW_IC_COMP_TYPE		0xfc
75 #define DW_IC_COMP_TYPE_VALUE	0x44570140
76 
77 #define DW_IC_INTR_RX_UNDER	0x001
78 #define DW_IC_INTR_RX_OVER	0x002
79 #define DW_IC_INTR_RX_FULL	0x004
80 #define DW_IC_INTR_TX_OVER	0x008
81 #define DW_IC_INTR_TX_EMPTY	0x010
82 #define DW_IC_INTR_RD_REQ	0x020
83 #define DW_IC_INTR_TX_ABRT	0x040
84 #define DW_IC_INTR_RX_DONE	0x080
85 #define DW_IC_INTR_ACTIVITY	0x100
86 #define DW_IC_INTR_STOP_DET	0x200
87 #define DW_IC_INTR_START_DET	0x400
88 #define DW_IC_INTR_GEN_CALL	0x800
89 #define DW_IC_INTR_RESTART_DET	0x1000
90 
91 #define DW_IC_INTR_DEFAULT_MASK		(DW_IC_INTR_RX_FULL | \
92 					 DW_IC_INTR_TX_ABRT | \
93 					 DW_IC_INTR_STOP_DET)
94 #define DW_IC_INTR_MASTER_MASK		(DW_IC_INTR_DEFAULT_MASK | \
95 					 DW_IC_INTR_TX_EMPTY)
96 #define DW_IC_INTR_SLAVE_MASK		(DW_IC_INTR_DEFAULT_MASK | \
97 					 DW_IC_INTR_RX_DONE | \
98 					 DW_IC_INTR_RX_UNDER | \
99 					 DW_IC_INTR_RD_REQ)
100 
101 #define DW_IC_STATUS_ACTIVITY		0x1
102 #define DW_IC_STATUS_TFE		BIT(2)
103 #define DW_IC_STATUS_MASTER_ACTIVITY	BIT(5)
104 #define DW_IC_STATUS_SLAVE_ACTIVITY	BIT(6)
105 
106 #define DW_IC_SDA_HOLD_RX_SHIFT		16
107 #define DW_IC_SDA_HOLD_RX_MASK		GENMASK(23, DW_IC_SDA_HOLD_RX_SHIFT)
108 
109 #define DW_IC_ERR_TX_ABRT	0x1
110 
111 #define DW_IC_TAR_10BITADDR_MASTER BIT(12)
112 
113 #define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH	(BIT(2) | BIT(3))
114 #define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK	GENMASK(3, 2)
115 
116 /*
117  * status codes
118  */
119 #define STATUS_IDLE			0x0
120 #define STATUS_WRITE_IN_PROGRESS	0x1
121 #define STATUS_READ_IN_PROGRESS		0x2
122 
123 #define TIMEOUT			20 /* ms */
124 
125 /*
126  * operation modes
127  */
128 #define DW_IC_MASTER		0
129 #define DW_IC_SLAVE		1
130 
131 /*
132  * Hardware abort codes from the DW_IC_TX_ABRT_SOURCE register
133  *
134  * Only expected abort codes are listed here
135  * refer to the datasheet for the full list
136  */
137 #define ABRT_7B_ADDR_NOACK	0
138 #define ABRT_10ADDR1_NOACK	1
139 #define ABRT_10ADDR2_NOACK	2
140 #define ABRT_TXDATA_NOACK	3
141 #define ABRT_GCALL_NOACK	4
142 #define ABRT_GCALL_READ		5
143 #define ABRT_SBYTE_ACKDET	7
144 #define ABRT_SBYTE_NORSTRT	9
145 #define ABRT_10B_RD_NORSTRT	10
146 #define ABRT_MASTER_DIS		11
147 #define ARB_LOST		12
148 #define ABRT_SLAVE_FLUSH_TXFIFO	13
149 #define ABRT_SLAVE_ARBLOST	14
150 #define ABRT_SLAVE_RD_INTX	15
151 
152 #define DW_IC_TX_ABRT_7B_ADDR_NOACK	(1UL << ABRT_7B_ADDR_NOACK)
153 #define DW_IC_TX_ABRT_10ADDR1_NOACK	(1UL << ABRT_10ADDR1_NOACK)
154 #define DW_IC_TX_ABRT_10ADDR2_NOACK	(1UL << ABRT_10ADDR2_NOACK)
155 #define DW_IC_TX_ABRT_TXDATA_NOACK	(1UL << ABRT_TXDATA_NOACK)
156 #define DW_IC_TX_ABRT_GCALL_NOACK	(1UL << ABRT_GCALL_NOACK)
157 #define DW_IC_TX_ABRT_GCALL_READ	(1UL << ABRT_GCALL_READ)
158 #define DW_IC_TX_ABRT_SBYTE_ACKDET	(1UL << ABRT_SBYTE_ACKDET)
159 #define DW_IC_TX_ABRT_SBYTE_NORSTRT	(1UL << ABRT_SBYTE_NORSTRT)
160 #define DW_IC_TX_ABRT_10B_RD_NORSTRT	(1UL << ABRT_10B_RD_NORSTRT)
161 #define DW_IC_TX_ABRT_MASTER_DIS	(1UL << ABRT_MASTER_DIS)
162 #define DW_IC_TX_ARB_LOST		(1UL << ARB_LOST)
163 #define DW_IC_RX_ABRT_SLAVE_RD_INTX	(1UL << ABRT_SLAVE_RD_INTX)
164 #define DW_IC_RX_ABRT_SLAVE_ARBLOST	(1UL << ABRT_SLAVE_ARBLOST)
165 #define DW_IC_RX_ABRT_SLAVE_FLUSH_TXFIFO	(1UL << ABRT_SLAVE_FLUSH_TXFIFO)
166 
167 #define DW_IC_TX_ABRT_NOACK		(DW_IC_TX_ABRT_7B_ADDR_NOACK | \
168 					 DW_IC_TX_ABRT_10ADDR1_NOACK | \
169 					 DW_IC_TX_ABRT_10ADDR2_NOACK | \
170 					 DW_IC_TX_ABRT_TXDATA_NOACK | \
171 					 DW_IC_TX_ABRT_GCALL_NOACK)
172 
173 
174 /**
175  * struct dw_i2c_dev - private i2c-designware data
176  * @dev: driver model device node
177  * @base: IO registers pointer
178  * @cmd_complete: tx completion indicator
179  * @clk: input reference clock
180  * @pclk: clock required to access the registers
181  * @slave: represent an I2C slave device
182  * @cmd_err: run time hadware error code
183  * @msgs: points to an array of messages currently being transferred
184  * @msgs_num: the number of elements in msgs
185  * @msg_write_idx: the element index of the current tx message in the msgs
186  *	array
187  * @tx_buf_len: the length of the current tx buffer
188  * @tx_buf: the current tx buffer
189  * @msg_read_idx: the element index of the current rx message in the msgs
190  *	array
191  * @rx_buf_len: the length of the current rx buffer
192  * @rx_buf: the current rx buffer
193  * @msg_err: error status of the current transfer
194  * @status: i2c master status, one of STATUS_*
195  * @abort_source: copy of the TX_ABRT_SOURCE register
196  * @irq: interrupt number for the i2c master
197  * @adapter: i2c subsystem adapter node
198  * @slave_cfg: configuration for the slave device
199  * @tx_fifo_depth: depth of the hardware tx fifo
200  * @rx_fifo_depth: depth of the hardware rx fifo
201  * @rx_outstanding: current master-rx elements in tx fifo
202  * @timings: bus clock frequency, SDA hold and other timings
203  * @sda_hold_time: SDA hold value
204  * @ss_hcnt: standard speed HCNT value
205  * @ss_lcnt: standard speed LCNT value
206  * @fs_hcnt: fast speed HCNT value
207  * @fs_lcnt: fast speed LCNT value
208  * @fp_hcnt: fast plus HCNT value
209  * @fp_lcnt: fast plus LCNT value
210  * @hs_hcnt: high speed HCNT value
211  * @hs_lcnt: high speed LCNT value
212  * @acquire_lock: function to acquire a hardware lock on the bus
213  * @release_lock: function to release a hardware lock on the bus
214  * @shared_with_punit: true if this bus is shared with the SoCs PUNIT
215  * @disable: function to disable the controller
216  * @disable_int: function to disable all interrupts
217  * @init: function to initialize the I2C hardware
218  * @mode: operation mode - DW_IC_MASTER or DW_IC_SLAVE
219  * @suspended: set to true if the controller is suspended
220  *
221  * HCNT and LCNT parameters can be used if the platform knows more accurate
222  * values than the one computed based only on the input clock frequency.
223  * Leave them to be %0 if not used.
224  */
225 struct dw_i2c_dev {
226 	struct device		*dev;
227 	void __iomem		*base;
228 	void __iomem		*ext;
229 	struct completion	cmd_complete;
230 	struct clk		*clk;
231 	struct clk		*pclk;
232 	struct reset_control	*rst;
233 	struct i2c_client		*slave;
234 	u32			(*get_clk_rate_khz) (struct dw_i2c_dev *dev);
235 	struct dw_pci_controller *controller;
236 	int			cmd_err;
237 	struct i2c_msg		*msgs;
238 	int			msgs_num;
239 	int			msg_write_idx;
240 	u32			tx_buf_len;
241 	u8			*tx_buf;
242 	int			msg_read_idx;
243 	u32			rx_buf_len;
244 	u8			*rx_buf;
245 	int			msg_err;
246 	unsigned int		status;
247 	u32			abort_source;
248 	int			irq;
249 	u32			flags;
250 	struct i2c_adapter	adapter;
251 	u32			functionality;
252 	u32			master_cfg;
253 	u32			slave_cfg;
254 	unsigned int		tx_fifo_depth;
255 	unsigned int		rx_fifo_depth;
256 	int			rx_outstanding;
257 	struct i2c_timings	timings;
258 	u32			sda_hold_time;
259 	u16			ss_hcnt;
260 	u16			ss_lcnt;
261 	u16			fs_hcnt;
262 	u16			fs_lcnt;
263 	u16			fp_hcnt;
264 	u16			fp_lcnt;
265 	u16			hs_hcnt;
266 	u16			hs_lcnt;
267 	int			(*acquire_lock)(void);
268 	void			(*release_lock)(void);
269 	bool			shared_with_punit;
270 	void			(*disable)(struct dw_i2c_dev *dev);
271 	void			(*disable_int)(struct dw_i2c_dev *dev);
272 	int			(*init)(struct dw_i2c_dev *dev);
273 	int			(*set_sda_hold_time)(struct dw_i2c_dev *dev);
274 	int			mode;
275 	struct i2c_bus_recovery_info rinfo;
276 	bool			suspended;
277 };
278 
279 #define ACCESS_SWAP		0x00000001
280 #define ACCESS_16BIT		0x00000002
281 #define ACCESS_INTR_MASK	0x00000004
282 #define ACCESS_NO_IRQ_SUSPEND	0x00000008
283 
284 #define MODEL_CHERRYTRAIL	0x00000100
285 #define MODEL_MSCC_OCELOT	0x00000200
286 #define MODEL_MASK		0x00000f00
287 
288 u32 dw_readl(struct dw_i2c_dev *dev, int offset);
289 void dw_writel(struct dw_i2c_dev *dev, u32 b, int offset);
290 int i2c_dw_set_reg_access(struct dw_i2c_dev *dev);
291 u32 i2c_dw_scl_hcnt(u32 ic_clk, u32 tSYMBOL, u32 tf, int cond, int offset);
292 u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset);
293 int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev);
294 unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev);
295 int i2c_dw_prepare_clk(struct dw_i2c_dev *dev, bool prepare);
296 int i2c_dw_acquire_lock(struct dw_i2c_dev *dev);
297 void i2c_dw_release_lock(struct dw_i2c_dev *dev);
298 int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev);
299 int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev);
300 u32 i2c_dw_func(struct i2c_adapter *adap);
301 void i2c_dw_disable(struct dw_i2c_dev *dev);
302 void i2c_dw_disable_int(struct dw_i2c_dev *dev);
303 
304 static inline void __i2c_dw_enable(struct dw_i2c_dev *dev)
305 {
306 	dw_writel(dev, 1, DW_IC_ENABLE);
307 }
308 
309 static inline void __i2c_dw_disable_nowait(struct dw_i2c_dev *dev)
310 {
311 	dw_writel(dev, 0, DW_IC_ENABLE);
312 }
313 
314 void __i2c_dw_disable(struct dw_i2c_dev *dev);
315 
316 extern u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev);
317 extern int i2c_dw_probe(struct dw_i2c_dev *dev);
318 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_SLAVE)
319 extern int i2c_dw_probe_slave(struct dw_i2c_dev *dev);
320 #else
321 static inline int i2c_dw_probe_slave(struct dw_i2c_dev *dev) { return -EINVAL; }
322 #endif
323 
324 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL)
325 extern int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev);
326 #else
327 static inline int i2c_dw_probe_lock_support(struct dw_i2c_dev *dev) { return 0; }
328 #endif
329