1 /*
2  * Synopsys DesignWare I2C adapter driver (master only).
3  *
4  * Based on the TI DAVINCI I2C adapter driver.
5  *
6  * Copyright (C) 2006 Texas Instruments.
7  * Copyright (C) 2007 MontaVista Software Inc.
8  * Copyright (C) 2009 Provigent Ltd.
9  *
10  * ----------------------------------------------------------------------------
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU General Public License as published by
14  * the Free Software Foundation; either version 2 of the License, or
15  * (at your option) any later version.
16  *
17  * This program is distributed in the hope that it will be useful,
18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  * GNU General Public License for more details.
21  * ----------------------------------------------------------------------------
22  *
23  */
24 
25 
26 #define DW_IC_CON_MASTER		0x1
27 #define DW_IC_CON_SPEED_STD		0x2
28 #define DW_IC_CON_SPEED_FAST		0x4
29 #define DW_IC_CON_SPEED_HIGH		0x6
30 #define DW_IC_CON_SPEED_MASK		0x6
31 #define DW_IC_CON_10BITADDR_MASTER	0x10
32 #define DW_IC_CON_RESTART_EN		0x20
33 #define DW_IC_CON_SLAVE_DISABLE		0x40
34 
35 
36 /**
37  * struct dw_i2c_dev - private i2c-designware data
38  * @dev: driver model device node
39  * @base: IO registers pointer
40  * @cmd_complete: tx completion indicator
41  * @clk: input reference clock
42  * @cmd_err: run time hadware error code
43  * @msgs: points to an array of messages currently being transfered
44  * @msgs_num: the number of elements in msgs
45  * @msg_write_idx: the element index of the current tx message in the msgs
46  *	array
47  * @tx_buf_len: the length of the current tx buffer
48  * @tx_buf: the current tx buffer
49  * @msg_read_idx: the element index of the current rx message in the msgs
50  *	array
51  * @rx_buf_len: the length of the current rx buffer
52  * @rx_buf: the current rx buffer
53  * @msg_err: error status of the current transfer
54  * @status: i2c master status, one of STATUS_*
55  * @abort_source: copy of the TX_ABRT_SOURCE register
56  * @irq: interrupt number for the i2c master
57  * @adapter: i2c subsystem adapter node
58  * @tx_fifo_depth: depth of the hardware tx fifo
59  * @rx_fifo_depth: depth of the hardware rx fifo
60  * @rx_outstanding: current master-rx elements in tx fifo
61  * @clk_freq: bus clock frequency
62  * @ss_hcnt: standard speed HCNT value
63  * @ss_lcnt: standard speed LCNT value
64  * @fs_hcnt: fast speed HCNT value
65  * @fs_lcnt: fast speed LCNT value
66  * @fp_hcnt: fast plus HCNT value
67  * @fp_lcnt: fast plus LCNT value
68  * @hs_hcnt: high speed HCNT value
69  * @hs_lcnt: high speed LCNT value
70  * @acquire_lock: function to acquire a hardware lock on the bus
71  * @release_lock: function to release a hardware lock on the bus
72  * @pm_runtime_disabled: true if pm runtime is disabled
73  *
74  * HCNT and LCNT parameters can be used if the platform knows more accurate
75  * values than the one computed based only on the input clock frequency.
76  * Leave them to be %0 if not used.
77  */
78 struct dw_i2c_dev {
79 	struct device		*dev;
80 	void __iomem		*base;
81 	struct completion	cmd_complete;
82 	struct clk		*clk;
83 	u32			(*get_clk_rate_khz) (struct dw_i2c_dev *dev);
84 	struct dw_pci_controller *controller;
85 	int			cmd_err;
86 	struct i2c_msg		*msgs;
87 	int			msgs_num;
88 	int			msg_write_idx;
89 	u32			tx_buf_len;
90 	u8			*tx_buf;
91 	int			msg_read_idx;
92 	u32			rx_buf_len;
93 	u8			*rx_buf;
94 	int			msg_err;
95 	unsigned int		status;
96 	u32			abort_source;
97 	int			irq;
98 	u32			accessor_flags;
99 	struct i2c_adapter	adapter;
100 	u32			functionality;
101 	u32			master_cfg;
102 	unsigned int		tx_fifo_depth;
103 	unsigned int		rx_fifo_depth;
104 	int			rx_outstanding;
105 	u32			clk_freq;
106 	u32			sda_hold_time;
107 	u32			sda_falling_time;
108 	u32			scl_falling_time;
109 	u16			ss_hcnt;
110 	u16			ss_lcnt;
111 	u16			fs_hcnt;
112 	u16			fs_lcnt;
113 	u16			fp_hcnt;
114 	u16			fp_lcnt;
115 	u16			hs_hcnt;
116 	u16			hs_lcnt;
117 	int			(*acquire_lock)(struct dw_i2c_dev *dev);
118 	void			(*release_lock)(struct dw_i2c_dev *dev);
119 	bool			pm_runtime_disabled;
120 	bool			dynamic_tar_update_enabled;
121 };
122 
123 #define ACCESS_SWAP		0x00000001
124 #define ACCESS_16BIT		0x00000002
125 #define ACCESS_INTR_MASK	0x00000004
126 
127 extern int i2c_dw_init(struct dw_i2c_dev *dev);
128 extern void i2c_dw_disable(struct dw_i2c_dev *dev);
129 extern void i2c_dw_disable_int(struct dw_i2c_dev *dev);
130 extern u32 i2c_dw_read_comp_param(struct dw_i2c_dev *dev);
131 extern int i2c_dw_probe(struct dw_i2c_dev *dev);
132 
133 #if IS_ENABLED(CONFIG_I2C_DESIGNWARE_BAYTRAIL)
134 extern int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev);
135 #else
136 static inline int i2c_dw_eval_lock_support(struct dw_i2c_dev *dev) { return 0; }
137 #endif
138