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13#include <linux/acpi.h>
14#include <linux/clk.h>
15#include <linux/delay.h>
16#include <linux/i2c.h>
17#include <linux/i2c-smbus.h>
18#include <linux/interrupt.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/of_irq.h>
22#include <linux/pci.h>
23
24#include "i2c-octeon-core.h"
25
26#define DRV_NAME "i2c-thunderx"
27
28#define PCI_DEVICE_ID_THUNDER_TWSI 0xa012
29
30#define SYS_FREQ_DEFAULT 700000000
31
32#define TWSI_INT_ENA_W1C 0x1028
33#define TWSI_INT_ENA_W1S 0x1030
34
35
36
37
38
39
40static void thunder_i2c_int_enable(struct octeon_i2c *i2c)
41{
42 octeon_i2c_writeq_flush(TWSI_INT_CORE_INT,
43 i2c->twsi_base + TWSI_INT_ENA_W1S);
44}
45
46
47
48
49static void thunder_i2c_int_disable(struct octeon_i2c *i2c)
50{
51 octeon_i2c_writeq_flush(TWSI_INT_CORE_INT,
52 i2c->twsi_base + TWSI_INT_ENA_W1C);
53}
54
55static void thunder_i2c_hlc_int_enable(struct octeon_i2c *i2c)
56{
57 octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT,
58 i2c->twsi_base + TWSI_INT_ENA_W1S);
59}
60
61static void thunder_i2c_hlc_int_disable(struct octeon_i2c *i2c)
62{
63 octeon_i2c_writeq_flush(TWSI_INT_ST_INT | TWSI_INT_TS_INT,
64 i2c->twsi_base + TWSI_INT_ENA_W1C);
65}
66
67static u32 thunderx_i2c_functionality(struct i2c_adapter *adap)
68{
69 return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK) |
70 I2C_FUNC_SMBUS_READ_BLOCK_DATA | I2C_SMBUS_BLOCK_PROC_CALL;
71}
72
73static const struct i2c_algorithm thunderx_i2c_algo = {
74 .master_xfer = octeon_i2c_xfer,
75 .functionality = thunderx_i2c_functionality,
76};
77
78static const struct i2c_adapter thunderx_i2c_ops = {
79 .owner = THIS_MODULE,
80 .name = "ThunderX adapter",
81 .algo = &thunderx_i2c_algo,
82};
83
84static void thunder_i2c_clock_enable(struct device *dev, struct octeon_i2c *i2c)
85{
86 int ret;
87
88 if (acpi_disabled) {
89
90 i2c->clk = clk_get(dev, NULL);
91 if (IS_ERR(i2c->clk)) {
92 i2c->clk = NULL;
93 goto skip;
94 }
95
96 ret = clk_prepare_enable(i2c->clk);
97 if (ret)
98 goto skip;
99 i2c->sys_freq = clk_get_rate(i2c->clk);
100 } else {
101
102 device_property_read_u32(dev, "sclk", &i2c->sys_freq);
103 }
104
105skip:
106 if (!i2c->sys_freq)
107 i2c->sys_freq = SYS_FREQ_DEFAULT;
108}
109
110static void thunder_i2c_clock_disable(struct device *dev, struct clk *clk)
111{
112 if (!clk)
113 return;
114 clk_disable_unprepare(clk);
115 clk_put(clk);
116}
117
118static int thunder_i2c_smbus_setup_of(struct octeon_i2c *i2c,
119 struct device_node *node)
120{
121 if (!node)
122 return -EINVAL;
123
124 i2c->alert_data.irq = irq_of_parse_and_map(node, 0);
125 if (!i2c->alert_data.irq)
126 return -EINVAL;
127
128 i2c->ara = i2c_setup_smbus_alert(&i2c->adap, &i2c->alert_data);
129 if (!i2c->ara)
130 return -ENODEV;
131 return 0;
132}
133
134static int thunder_i2c_smbus_setup(struct octeon_i2c *i2c,
135 struct device_node *node)
136{
137
138 if (!acpi_disabled)
139 return -EOPNOTSUPP;
140
141 return thunder_i2c_smbus_setup_of(i2c, node);
142}
143
144static void thunder_i2c_smbus_remove(struct octeon_i2c *i2c)
145{
146 i2c_unregister_device(i2c->ara);
147}
148
149static int thunder_i2c_probe_pci(struct pci_dev *pdev,
150 const struct pci_device_id *ent)
151{
152 struct device *dev = &pdev->dev;
153 struct octeon_i2c *i2c;
154 int ret;
155
156 i2c = devm_kzalloc(dev, sizeof(*i2c), GFP_KERNEL);
157 if (!i2c)
158 return -ENOMEM;
159
160 i2c->roff.sw_twsi = 0x1000;
161 i2c->roff.twsi_int = 0x1010;
162 i2c->roff.sw_twsi_ext = 0x1018;
163
164 i2c->dev = dev;
165 pci_set_drvdata(pdev, i2c);
166 ret = pcim_enable_device(pdev);
167 if (ret)
168 return ret;
169
170 ret = pci_request_regions(pdev, DRV_NAME);
171 if (ret)
172 return ret;
173
174 i2c->twsi_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0));
175 if (!i2c->twsi_base)
176 return -EINVAL;
177
178 thunder_i2c_clock_enable(dev, i2c);
179 ret = device_property_read_u32(dev, "clock-frequency", &i2c->twsi_freq);
180 if (ret)
181 i2c->twsi_freq = 100000;
182
183 init_waitqueue_head(&i2c->queue);
184
185 i2c->int_enable = thunder_i2c_int_enable;
186 i2c->int_disable = thunder_i2c_int_disable;
187 i2c->hlc_int_enable = thunder_i2c_hlc_int_enable;
188 i2c->hlc_int_disable = thunder_i2c_hlc_int_disable;
189
190 ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_MSIX);
191 if (ret < 0)
192 goto error;
193
194 ret = devm_request_irq(dev, pci_irq_vector(pdev, 0), octeon_i2c_isr, 0,
195 DRV_NAME, i2c);
196 if (ret)
197 goto error;
198
199 ret = octeon_i2c_init_lowlevel(i2c);
200 if (ret)
201 goto error;
202
203 octeon_i2c_set_clock(i2c);
204
205 i2c->adap = thunderx_i2c_ops;
206 i2c->adap.retries = 5;
207 i2c->adap.class = I2C_CLASS_HWMON;
208 i2c->adap.bus_recovery_info = &octeon_i2c_recovery_info;
209 i2c->adap.dev.parent = dev;
210 i2c->adap.dev.of_node = pdev->dev.of_node;
211 snprintf(i2c->adap.name, sizeof(i2c->adap.name),
212 "Cavium ThunderX i2c adapter at %s", dev_name(dev));
213 i2c_set_adapdata(&i2c->adap, i2c);
214
215 ret = i2c_add_adapter(&i2c->adap);
216 if (ret)
217 goto error;
218
219 dev_info(i2c->dev, "Probed. Set system clock to %u\n", i2c->sys_freq);
220
221 ret = thunder_i2c_smbus_setup(i2c, pdev->dev.of_node);
222 if (ret)
223 dev_info(dev, "SMBUS alert not active on this bus\n");
224
225 return 0;
226
227error:
228 thunder_i2c_clock_disable(dev, i2c->clk);
229 return ret;
230}
231
232static void thunder_i2c_remove_pci(struct pci_dev *pdev)
233{
234 struct octeon_i2c *i2c = pci_get_drvdata(pdev);
235
236 thunder_i2c_smbus_remove(i2c);
237 thunder_i2c_clock_disable(&pdev->dev, i2c->clk);
238 i2c_del_adapter(&i2c->adap);
239}
240
241static const struct pci_device_id thunder_i2c_pci_id_table[] = {
242 { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, PCI_DEVICE_ID_THUNDER_TWSI) },
243 { 0, }
244};
245
246MODULE_DEVICE_TABLE(pci, thunder_i2c_pci_id_table);
247
248static struct pci_driver thunder_i2c_pci_driver = {
249 .name = DRV_NAME,
250 .id_table = thunder_i2c_pci_id_table,
251 .probe = thunder_i2c_probe_pci,
252 .remove = thunder_i2c_remove_pci,
253};
254
255module_pci_driver(thunder_i2c_pci_driver);
256
257MODULE_LICENSE("GPL");
258MODULE_AUTHOR("Fred Martin <fmartin@caviumnetworks.com>");
259MODULE_DESCRIPTION("I2C-Bus adapter for Cavium ThunderX SOC");
260
