1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Intel Quark MFD PCI driver for I2C & GPIO
4 *
5 * Copyright(c) 2014 Intel Corporation.
6 *
7 * Intel Quark PCI device for I2C and GPIO controller sharing the same
8 * PCI function. This PCI driver will split the 2 devices into their
9 * respective drivers.
10 */
11
12#include <linux/kernel.h>
13#include <linux/module.h>
14#include <linux/pci.h>
15#include <linux/mfd/core.h>
16#include <linux/clkdev.h>
17#include <linux/clk-provider.h>
18#include <linux/dmi.h>
19#include <linux/i2c.h>
20#include <linux/property.h>
21
22/* PCI BAR for register base address */
23#define MFD_I2C_BAR 0
24#define MFD_GPIO_BAR 1
25
26/* ACPI _ADR value to match the child node */
27#define MFD_ACPI_MATCH_GPIO 0ULL
28#define MFD_ACPI_MATCH_I2C 1ULL
29
30#define INTEL_QUARK_IORES_MEM 0
31#define INTEL_QUARK_IORES_IRQ 1
32
33#define INTEL_QUARK_I2C_CONTROLLER_CLK "i2c_designware.0"
34
35/* The Quark I2C controller source clock */
36#define INTEL_QUARK_I2C_CLK_HZ 33000000
37
38struct intel_quark_mfd {
39 struct clk *i2c_clk;
40 struct clk_lookup *i2c_clk_lookup;
41};
42
43static const struct property_entry intel_quark_i2c_controller_standard_properties[] = {
44 PROPERTY_ENTRY_U32("clock-frequency", I2C_MAX_STANDARD_MODE_FREQ),
45 { }
46};
47
48static const struct software_node intel_quark_i2c_controller_standard_node = {
49 .name = "intel-quark-i2c-controller",
50 .properties = intel_quark_i2c_controller_standard_properties,
51};
52
53static const struct property_entry intel_quark_i2c_controller_fast_properties[] = {
54 PROPERTY_ENTRY_U32("clock-frequency", I2C_MAX_FAST_MODE_FREQ),
55 { }
56};
57
58static const struct software_node intel_quark_i2c_controller_fast_node = {
59 .name = "intel-quark-i2c-controller",
60 .properties = intel_quark_i2c_controller_fast_properties,
61};
62
63static const struct dmi_system_id dmi_platform_info[] = {
64 {
65 .matches = {
66 DMI_EXACT_MATCH(DMI_BOARD_NAME, "Galileo"),
67 },
68 .driver_data = (void *)&intel_quark_i2c_controller_standard_node,
69 },
70 {
71 .matches = {
72 DMI_EXACT_MATCH(DMI_BOARD_NAME, "GalileoGen2"),
73 },
74 .driver_data = (void *)&intel_quark_i2c_controller_fast_node,
75 },
76 {
77 .matches = {
78 DMI_EXACT_MATCH(DMI_BOARD_NAME, "SIMATIC IOT2000"),
79 },
80 .driver_data = (void *)&intel_quark_i2c_controller_fast_node,
81 },
82 {}
83};
84
85/* This is used as a place holder and will be modified at run-time */
86static struct resource intel_quark_i2c_res[] = {
87 [INTEL_QUARK_IORES_MEM] = {
88 .flags = IORESOURCE_MEM,
89 },
90 [INTEL_QUARK_IORES_IRQ] = {
91 .flags = IORESOURCE_IRQ,
92 },
93};
94
95static struct mfd_cell_acpi_match intel_quark_acpi_match_i2c = {
96 .adr = MFD_ACPI_MATCH_I2C,
97};
98
99/* This is used as a place holder and will be modified at run-time */
100static struct resource intel_quark_gpio_res[] = {
101 [INTEL_QUARK_IORES_MEM] = {
102 .flags = IORESOURCE_MEM,
103 },
104 [INTEL_QUARK_IORES_IRQ] = {
105 .flags = IORESOURCE_IRQ,
106 },
107};
108
109static struct mfd_cell_acpi_match intel_quark_acpi_match_gpio = {
110 .adr = MFD_ACPI_MATCH_GPIO,
111};
112
113static const struct software_node intel_quark_gpio_controller_node = {
114 .name = "intel-quark-gpio-controller",
115};
116
117static const struct property_entry intel_quark_gpio_portA_properties[] = {
118 PROPERTY_ENTRY_U32("reg", 0),
119 PROPERTY_ENTRY_U32("snps,nr-gpios", 8),
120 PROPERTY_ENTRY_U32("gpio-base", 8),
121 { }
122};
123
124static const struct software_node intel_quark_gpio_portA_node = {
125 .name = "portA",
126 .parent = &intel_quark_gpio_controller_node,
127 .properties = intel_quark_gpio_portA_properties,
128};
129
130static const struct software_node *intel_quark_gpio_node_group[] = {
131 &intel_quark_gpio_controller_node,
132 &intel_quark_gpio_portA_node,
133 NULL
134};
135
136static struct mfd_cell intel_quark_mfd_cells[] = {
137 [MFD_I2C_BAR] = {
138 .id = MFD_I2C_BAR,
139 .name = "i2c_designware",
140 .acpi_match = &intel_quark_acpi_match_i2c,
141 .num_resources = ARRAY_SIZE(intel_quark_i2c_res),
142 .resources = intel_quark_i2c_res,
143 .ignore_resource_conflicts = true,
144 },
145 [MFD_GPIO_BAR] = {
146 .id = MFD_GPIO_BAR,
147 .name = "gpio-dwapb",
148 .acpi_match = &intel_quark_acpi_match_gpio,
149 .num_resources = ARRAY_SIZE(intel_quark_gpio_res),
150 .resources = intel_quark_gpio_res,
151 .ignore_resource_conflicts = true,
152 },
153};
154
155static const struct pci_device_id intel_quark_mfd_ids[] = {
156 { PCI_VDEVICE(INTEL, 0x0934), },
157 {},
158};
159MODULE_DEVICE_TABLE(pci, intel_quark_mfd_ids);
160
161static int intel_quark_register_i2c_clk(struct device *dev)
162{
163 struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
164 struct clk *i2c_clk;
165
166 i2c_clk = clk_register_fixed_rate(dev,
167 INTEL_QUARK_I2C_CONTROLLER_CLK, NULL,
168 flags: 0, INTEL_QUARK_I2C_CLK_HZ);
169 if (IS_ERR(ptr: i2c_clk))
170 return PTR_ERR(ptr: i2c_clk);
171
172 quark_mfd->i2c_clk = i2c_clk;
173 quark_mfd->i2c_clk_lookup = clkdev_create(clk: i2c_clk, NULL,
174 INTEL_QUARK_I2C_CONTROLLER_CLK);
175
176 if (!quark_mfd->i2c_clk_lookup) {
177 clk_unregister(clk: quark_mfd->i2c_clk);
178 dev_err(dev, "Fixed clk register failed\n");
179 return -ENOMEM;
180 }
181
182 return 0;
183}
184
185static void intel_quark_unregister_i2c_clk(struct device *dev)
186{
187 struct intel_quark_mfd *quark_mfd = dev_get_drvdata(dev);
188
189 if (!quark_mfd->i2c_clk_lookup)
190 return;
191
192 clkdev_drop(cl: quark_mfd->i2c_clk_lookup);
193 clk_unregister(clk: quark_mfd->i2c_clk);
194}
195
196static int intel_quark_i2c_setup(struct pci_dev *pdev)
197{
198 struct mfd_cell *cell = &intel_quark_mfd_cells[MFD_I2C_BAR];
199 struct resource *res = intel_quark_i2c_res;
200 const struct dmi_system_id *dmi_id;
201
202 res[INTEL_QUARK_IORES_MEM].start = pci_resource_start(pdev, MFD_I2C_BAR);
203 res[INTEL_QUARK_IORES_MEM].end = pci_resource_end(pdev, MFD_I2C_BAR);
204
205 res[INTEL_QUARK_IORES_IRQ].start = pci_irq_vector(dev: pdev, nr: 0);
206 res[INTEL_QUARK_IORES_IRQ].end = pci_irq_vector(dev: pdev, nr: 0);
207
208 /* Normal mode by default */
209 cell->swnode = &intel_quark_i2c_controller_standard_node;
210
211 dmi_id = dmi_first_match(list: dmi_platform_info);
212 if (dmi_id)
213 cell->swnode = (struct software_node *)dmi_id->driver_data;
214
215 return 0;
216}
217
218static int intel_quark_gpio_setup(struct pci_dev *pdev)
219{
220 struct mfd_cell *cell = &intel_quark_mfd_cells[MFD_GPIO_BAR];
221 struct resource *res = intel_quark_gpio_res;
222 int ret;
223
224 res[INTEL_QUARK_IORES_MEM].start = pci_resource_start(pdev, MFD_GPIO_BAR);
225 res[INTEL_QUARK_IORES_MEM].end = pci_resource_end(pdev, MFD_GPIO_BAR);
226
227 res[INTEL_QUARK_IORES_IRQ].start = pci_irq_vector(dev: pdev, nr: 0);
228 res[INTEL_QUARK_IORES_IRQ].end = pci_irq_vector(dev: pdev, nr: 0);
229
230 ret = software_node_register_node_group(node_group: intel_quark_gpio_node_group);
231 if (ret)
232 return ret;
233
234 cell->swnode = &intel_quark_gpio_controller_node;
235 return 0;
236}
237
238static int intel_quark_mfd_probe(struct pci_dev *pdev,
239 const struct pci_device_id *id)
240{
241 struct intel_quark_mfd *quark_mfd;
242 int ret;
243
244 ret = pcim_enable_device(pdev);
245 if (ret)
246 return ret;
247
248 quark_mfd = devm_kzalloc(dev: &pdev->dev, size: sizeof(*quark_mfd), GFP_KERNEL);
249 if (!quark_mfd)
250 return -ENOMEM;
251
252 dev_set_drvdata(dev: &pdev->dev, data: quark_mfd);
253
254 ret = intel_quark_register_i2c_clk(dev: &pdev->dev);
255 if (ret)
256 return ret;
257
258 pci_set_master(dev: pdev);
259
260 /* This driver only requires 1 IRQ vector */
261 ret = pci_alloc_irq_vectors(dev: pdev, min_vecs: 1, max_vecs: 1, PCI_IRQ_ALL_TYPES);
262 if (ret < 0)
263 goto err_unregister_i2c_clk;
264
265 ret = intel_quark_i2c_setup(pdev);
266 if (ret)
267 goto err_free_irq_vectors;
268
269 ret = intel_quark_gpio_setup(pdev);
270 if (ret)
271 goto err_free_irq_vectors;
272
273 ret = mfd_add_devices(parent: &pdev->dev, id: 0, cells: intel_quark_mfd_cells,
274 ARRAY_SIZE(intel_quark_mfd_cells), NULL, irq_base: 0,
275 NULL);
276 if (ret)
277 goto err_unregister_gpio_node_group;
278
279 return 0;
280
281err_unregister_gpio_node_group:
282 software_node_unregister_node_group(node_group: intel_quark_gpio_node_group);
283err_free_irq_vectors:
284 pci_free_irq_vectors(dev: pdev);
285err_unregister_i2c_clk:
286 intel_quark_unregister_i2c_clk(dev: &pdev->dev);
287 return ret;
288}
289
290static void intel_quark_mfd_remove(struct pci_dev *pdev)
291{
292 mfd_remove_devices(parent: &pdev->dev);
293 software_node_unregister_node_group(node_group: intel_quark_gpio_node_group);
294 pci_free_irq_vectors(dev: pdev);
295 intel_quark_unregister_i2c_clk(dev: &pdev->dev);
296}
297
298static struct pci_driver intel_quark_mfd_driver = {
299 .name = "intel_quark_mfd_i2c_gpio",
300 .id_table = intel_quark_mfd_ids,
301 .probe = intel_quark_mfd_probe,
302 .remove = intel_quark_mfd_remove,
303};
304
305module_pci_driver(intel_quark_mfd_driver);
306
307MODULE_AUTHOR("Raymond Tan <raymond.tan@intel.com>");
308MODULE_DESCRIPTION("Intel Quark MFD PCI driver for I2C & GPIO");
309MODULE_LICENSE("GPL v2");
310

source code of linux/drivers/mfd/intel_quark_i2c_gpio.c