2 * Synopsys DesignWare I2C adapter driver (master only).
4 * Based on the TI DAVINCI I2C adapter driver.
6 * Copyright (C) 2006 Texas Instruments.
7 * Copyright (C) 2007 MontaVista Software Inc.
8 * Copyright (C) 2009 Provigent Ltd.
10 * ----------------------------------------------------------------------------
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.
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 * ----------------------------------------------------------------------------
24 #include <linux/kernel.h>
25 #include <linux/module.h>
26 #include <linux/delay.h>
27 #include <linux/i2c.h>
28 #include <linux/clk.h>
29 #include <linux/clk-provider.h>
30 #include <linux/errno.h>
31 #include <linux/sched.h>
32 #include <linux/err.h>
33 #include <linux/interrupt.h>
35 #include <linux/platform_device.h>
37 #include <linux/pm_runtime.h>
39 #include <linux/slab.h>
40 #include <linux/acpi.h>
41 #include <linux/platform_data/i2c-designware.h>
42 #include "i2c-designware-core.h"
44 static struct i2c_algorithm i2c_dw_algo
= {
45 .master_xfer
= i2c_dw_xfer
,
46 .functionality
= i2c_dw_func
,
48 static u32
i2c_dw_get_clk_rate_khz(struct dw_i2c_dev
*dev
)
50 return clk_get_rate(dev
->clk
)/1000;
54 static void dw_i2c_acpi_params(struct platform_device
*pdev
, char method
[],
55 u16
*hcnt
, u16
*lcnt
, u32
*sda_hold
)
57 struct acpi_buffer buf
= { ACPI_ALLOCATE_BUFFER
};
58 acpi_handle handle
= ACPI_HANDLE(&pdev
->dev
);
59 union acpi_object
*obj
;
61 if (ACPI_FAILURE(acpi_evaluate_object(handle
, method
, NULL
, &buf
)))
64 obj
= (union acpi_object
*)buf
.pointer
;
65 if (obj
->type
== ACPI_TYPE_PACKAGE
&& obj
->package
.count
== 3) {
66 const union acpi_object
*objs
= obj
->package
.elements
;
68 *hcnt
= (u16
)objs
[0].integer
.value
;
69 *lcnt
= (u16
)objs
[1].integer
.value
;
71 *sda_hold
= (u32
)objs
[2].integer
.value
;
77 static int dw_i2c_acpi_configure(struct platform_device
*pdev
)
79 struct dw_i2c_dev
*dev
= platform_get_drvdata(pdev
);
80 const struct acpi_device_id
*id
;
83 dev
->tx_fifo_depth
= 32;
84 dev
->rx_fifo_depth
= 32;
87 * Try to get SDA hold time and *CNT values from an ACPI method if
88 * it exists for both supported speed modes.
90 dw_i2c_acpi_params(pdev
, "SSCN", &dev
->ss_hcnt
, &dev
->ss_lcnt
, NULL
);
91 dw_i2c_acpi_params(pdev
, "FMCN", &dev
->fs_hcnt
, &dev
->fs_lcnt
,
95 * Provide a way for Designware I2C host controllers that are not
96 * based on Intel LPSS to specify their input clock frequency via
99 id
= acpi_match_device(pdev
->dev
.driver
->acpi_match_table
, &pdev
->dev
);
100 if (id
&& id
->driver_data
)
101 clk_register_fixed_rate(&pdev
->dev
, dev_name(&pdev
->dev
), NULL
,
102 CLK_IS_ROOT
, id
->driver_data
);
107 static void dw_i2c_acpi_unconfigure(struct platform_device
*pdev
)
109 struct dw_i2c_dev
*dev
= platform_get_drvdata(pdev
);
110 const struct acpi_device_id
*id
;
112 id
= acpi_match_device(pdev
->dev
.driver
->acpi_match_table
, &pdev
->dev
);
113 if (id
&& id
->driver_data
)
114 clk_unregister(dev
->clk
);
117 static const struct acpi_device_id dw_i2c_acpi_match
[] = {
124 { "AMD0010", 133 * 1000 * 1000 },
127 MODULE_DEVICE_TABLE(acpi
, dw_i2c_acpi_match
);
129 static inline int dw_i2c_acpi_configure(struct platform_device
*pdev
)
133 static inline void dw_i2c_acpi_unconfigure(struct platform_device
*pdev
) { }
136 static int dw_i2c_probe(struct platform_device
*pdev
)
138 struct dw_i2c_dev
*dev
;
139 struct i2c_adapter
*adap
;
140 struct resource
*mem
;
141 struct dw_i2c_platform_data
*pdata
;
143 u32 clk_freq
, ht
= 0;
145 irq
= platform_get_irq(pdev
, 0);
149 dev
= devm_kzalloc(&pdev
->dev
, sizeof(struct dw_i2c_dev
), GFP_KERNEL
);
153 mem
= platform_get_resource(pdev
, IORESOURCE_MEM
, 0);
154 dev
->base
= devm_ioremap_resource(&pdev
->dev
, mem
);
155 if (IS_ERR(dev
->base
))
156 return PTR_ERR(dev
->base
);
158 init_completion(&dev
->cmd_complete
);
159 mutex_init(&dev
->lock
);
160 dev
->dev
= &pdev
->dev
;
162 platform_set_drvdata(pdev
, dev
);
164 /* fast mode by default because of legacy reasons */
167 if (has_acpi_companion(&pdev
->dev
)) {
168 dw_i2c_acpi_configure(pdev
);
169 } else if (pdev
->dev
.of_node
) {
170 of_property_read_u32(pdev
->dev
.of_node
,
171 "i2c-sda-hold-time-ns", &ht
);
173 of_property_read_u32(pdev
->dev
.of_node
,
174 "i2c-sda-falling-time-ns",
175 &dev
->sda_falling_time
);
176 of_property_read_u32(pdev
->dev
.of_node
,
177 "i2c-scl-falling-time-ns",
178 &dev
->scl_falling_time
);
180 of_property_read_u32(pdev
->dev
.of_node
, "clock-frequency",
183 /* Only standard mode at 100kHz and fast mode at 400kHz
186 if (clk_freq
!= 100000 && clk_freq
!= 400000) {
187 dev_err(&pdev
->dev
, "Only 100kHz and 400kHz supported");
191 pdata
= dev_get_platdata(&pdev
->dev
);
193 clk_freq
= pdata
->i2c_scl_freq
;
196 r
= i2c_dw_eval_lock_support(dev
);
202 I2C_FUNC_10BIT_ADDR
|
203 I2C_FUNC_SMBUS_BYTE
|
204 I2C_FUNC_SMBUS_BYTE_DATA
|
205 I2C_FUNC_SMBUS_WORD_DATA
|
206 I2C_FUNC_SMBUS_I2C_BLOCK
;
207 if (clk_freq
== 100000)
208 dev
->master_cfg
= DW_IC_CON_MASTER
| DW_IC_CON_SLAVE_DISABLE
|
209 DW_IC_CON_RESTART_EN
| DW_IC_CON_SPEED_STD
;
211 dev
->master_cfg
= DW_IC_CON_MASTER
| DW_IC_CON_SLAVE_DISABLE
|
212 DW_IC_CON_RESTART_EN
| DW_IC_CON_SPEED_FAST
;
214 dev
->clk
= devm_clk_get(&pdev
->dev
, NULL
);
215 dev
->get_clk_rate_khz
= i2c_dw_get_clk_rate_khz
;
216 if (IS_ERR(dev
->clk
))
217 return PTR_ERR(dev
->clk
);
218 clk_prepare_enable(dev
->clk
);
220 if (!dev
->sda_hold_time
&& ht
) {
221 u32 ic_clk
= dev
->get_clk_rate_khz(dev
);
223 dev
->sda_hold_time
= div_u64((u64
)ic_clk
* ht
+ 500000,
227 if (!dev
->tx_fifo_depth
) {
228 u32 param1
= i2c_dw_read_comp_param(dev
);
230 dev
->tx_fifo_depth
= ((param1
>> 16) & 0xff) + 1;
231 dev
->rx_fifo_depth
= ((param1
>> 8) & 0xff) + 1;
232 dev
->adapter
.nr
= pdev
->id
;
234 r
= i2c_dw_init(dev
);
238 i2c_dw_disable_int(dev
);
239 r
= devm_request_irq(&pdev
->dev
, dev
->irq
, i2c_dw_isr
, IRQF_SHARED
,
242 dev_err(&pdev
->dev
, "failure requesting irq %i\n", dev
->irq
);
246 adap
= &dev
->adapter
;
247 i2c_set_adapdata(adap
, dev
);
248 adap
->owner
= THIS_MODULE
;
249 adap
->class = I2C_CLASS_DEPRECATED
;
250 strlcpy(adap
->name
, "Synopsys DesignWare I2C adapter",
252 adap
->algo
= &i2c_dw_algo
;
253 adap
->dev
.parent
= &pdev
->dev
;
254 adap
->dev
.of_node
= pdev
->dev
.of_node
;
256 r
= i2c_add_numbered_adapter(adap
);
258 dev_err(&pdev
->dev
, "failure adding adapter\n");
262 if (dev
->pm_runtime_disabled
) {
263 pm_runtime_forbid(&pdev
->dev
);
265 pm_runtime_set_autosuspend_delay(&pdev
->dev
, 1000);
266 pm_runtime_use_autosuspend(&pdev
->dev
);
267 pm_runtime_set_active(&pdev
->dev
);
268 pm_runtime_enable(&pdev
->dev
);
274 static int dw_i2c_remove(struct platform_device
*pdev
)
276 struct dw_i2c_dev
*dev
= platform_get_drvdata(pdev
);
278 pm_runtime_get_sync(&pdev
->dev
);
280 i2c_del_adapter(&dev
->adapter
);
284 pm_runtime_dont_use_autosuspend(&pdev
->dev
);
285 pm_runtime_put_sync(&pdev
->dev
);
286 pm_runtime_disable(&pdev
->dev
);
288 if (has_acpi_companion(&pdev
->dev
))
289 dw_i2c_acpi_unconfigure(pdev
);
295 static const struct of_device_id dw_i2c_of_match
[] = {
296 { .compatible
= "snps,designware-i2c", },
299 MODULE_DEVICE_TABLE(of
, dw_i2c_of_match
);
302 #ifdef CONFIG_PM_SLEEP
303 static int dw_i2c_prepare(struct device
*dev
)
305 return pm_runtime_suspended(dev
);
308 static void dw_i2c_complete(struct device
*dev
)
310 if (dev
->power
.direct_complete
)
311 pm_request_resume(dev
);
314 #define dw_i2c_prepare NULL
315 #define dw_i2c_complete NULL
319 static int dw_i2c_suspend(struct device
*dev
)
321 struct platform_device
*pdev
= to_platform_device(dev
);
322 struct dw_i2c_dev
*i_dev
= platform_get_drvdata(pdev
);
324 i2c_dw_disable(i_dev
);
325 clk_disable_unprepare(i_dev
->clk
);
330 static int dw_i2c_resume(struct device
*dev
)
332 struct platform_device
*pdev
= to_platform_device(dev
);
333 struct dw_i2c_dev
*i_dev
= platform_get_drvdata(pdev
);
335 clk_prepare_enable(i_dev
->clk
);
337 if (!i_dev
->pm_runtime_disabled
)
343 static const struct dev_pm_ops dw_i2c_dev_pm_ops
= {
344 .prepare
= dw_i2c_prepare
,
345 .complete
= dw_i2c_complete
,
346 SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_suspend
, dw_i2c_resume
)
347 SET_RUNTIME_PM_OPS(dw_i2c_suspend
, dw_i2c_resume
, NULL
)
350 #define DW_I2C_DEV_PMOPS (&dw_i2c_dev_pm_ops)
352 #define DW_I2C_DEV_PMOPS NULL
355 /* work with hotplug and coldplug */
356 MODULE_ALIAS("platform:i2c_designware");
358 static struct platform_driver dw_i2c_driver
= {
359 .probe
= dw_i2c_probe
,
360 .remove
= dw_i2c_remove
,
362 .name
= "i2c_designware",
363 .of_match_table
= of_match_ptr(dw_i2c_of_match
),
364 .acpi_match_table
= ACPI_PTR(dw_i2c_acpi_match
),
365 .pm
= DW_I2C_DEV_PMOPS
,
369 static int __init
dw_i2c_init_driver(void)
371 return platform_driver_register(&dw_i2c_driver
);
373 subsys_initcall(dw_i2c_init_driver
);
375 static void __exit
dw_i2c_exit_driver(void)
377 platform_driver_unregister(&dw_i2c_driver
);
379 module_exit(dw_i2c_exit_driver
);
381 MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
382 MODULE_DESCRIPTION("Synopsys DesignWare I2C bus adapter");
383 MODULE_LICENSE("GPL");