drm: Import driver for the sil164 I2C TMDS transmitter.

sil164 transmitters are used for DVI outputs on Intel/nvidia and ATI setups.

So far only nouveau can use this driver.

Signed-off-by: Francisco Jerez <currojerez@riseup.net>
Tested-by: Patrice Mandin <patmandin@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/i2c/sil164_drv.c b/drivers/gpu/drm/i2c/sil164_drv.c
new file mode 100644
index 0000000..0b67732
--- /dev/null
+++ b/drivers/gpu/drm/i2c/sil164_drv.c
@@ -0,0 +1,462 @@
+/*
+ * Copyright (C) 2010 Francisco Jerez.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial
+ * portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+ * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+#include "drmP.h"
+#include "drm_crtc_helper.h"
+#include "drm_encoder_slave.h"
+#include "i2c/sil164.h"
+
+struct sil164_priv {
+	struct sil164_encoder_params config;
+	struct i2c_client *duallink_slave;
+
+	uint8_t saved_state[0x10];
+	uint8_t saved_slave_state[0x10];
+};
+
+#define to_sil164_priv(x) \
+	((struct sil164_priv *)to_encoder_slave(x)->slave_priv)
+
+#define sil164_dbg(client, format, ...) do {				\
+		if (drm_debug & DRM_UT_KMS)				\
+			dev_printk(KERN_DEBUG, &client->dev,		\
+				   "%s: " format, __func__, ## __VA_ARGS__); \
+	} while (0)
+#define sil164_info(client, format, ...)		\
+	dev_info(&client->dev, format, __VA_ARGS__)
+#define sil164_err(client, format, ...)			\
+	dev_err(&client->dev, format, __VA_ARGS__)
+
+#define SIL164_I2C_ADDR_MASTER			0x38
+#define SIL164_I2C_ADDR_SLAVE			0x39
+
+/* HW register definitions */
+
+#define SIL164_VENDOR_LO			0x0
+#define SIL164_VENDOR_HI			0x1
+#define SIL164_DEVICE_LO			0x2
+#define SIL164_DEVICE_HI			0x3
+#define SIL164_REVISION				0x4
+#define SIL164_FREQ_MIN				0x6
+#define SIL164_FREQ_MAX				0x7
+#define SIL164_CONTROL0				0x8
+#  define SIL164_CONTROL0_POWER_ON		0x01
+#  define SIL164_CONTROL0_EDGE_RISING		0x02
+#  define SIL164_CONTROL0_INPUT_24BIT		0x04
+#  define SIL164_CONTROL0_DUAL_EDGE		0x08
+#  define SIL164_CONTROL0_HSYNC_ON		0x10
+#  define SIL164_CONTROL0_VSYNC_ON		0x20
+#define SIL164_DETECT				0x9
+#  define SIL164_DETECT_INTR_STAT		0x01
+#  define SIL164_DETECT_HOTPLUG_STAT		0x02
+#  define SIL164_DETECT_RECEIVER_STAT		0x04
+#  define SIL164_DETECT_INTR_MODE_RECEIVER	0x00
+#  define SIL164_DETECT_INTR_MODE_HOTPLUG	0x08
+#  define SIL164_DETECT_OUT_MODE_HIGH		0x00
+#  define SIL164_DETECT_OUT_MODE_INTR		0x10
+#  define SIL164_DETECT_OUT_MODE_RECEIVER	0x20
+#  define SIL164_DETECT_OUT_MODE_HOTPLUG	0x30
+#  define SIL164_DETECT_VSWING_STAT		0x80
+#define SIL164_CONTROL1				0xa
+#  define SIL164_CONTROL1_DESKEW_ENABLE		0x10
+#  define SIL164_CONTROL1_DESKEW_INCR_SHIFT	5
+#define SIL164_GPIO				0xb
+#define SIL164_CONTROL2				0xc
+#  define SIL164_CONTROL2_FILTER_ENABLE		0x01
+#  define SIL164_CONTROL2_FILTER_SETTING_SHIFT	1
+#  define SIL164_CONTROL2_DUALLINK_MASTER	0x40
+#  define SIL164_CONTROL2_SYNC_CONT		0x80
+#define SIL164_DUALLINK				0xd
+#  define SIL164_DUALLINK_ENABLE		0x10
+#  define SIL164_DUALLINK_SKEW_SHIFT		5
+#define SIL164_PLLZONE				0xe
+#  define SIL164_PLLZONE_STAT			0x08
+#  define SIL164_PLLZONE_FORCE_ON		0x10
+#  define SIL164_PLLZONE_FORCE_HIGH		0x20
+
+/* HW access functions */
+
+static void
+sil164_write(struct i2c_client *client, uint8_t addr, uint8_t val)
+{
+	uint8_t buf[] = {addr, val};
+	int ret;
+
+	ret = i2c_master_send(client, buf, ARRAY_SIZE(buf));
+	if (ret < 0)
+		sil164_err(client, "Error %d writing to subaddress 0x%x\n",
+			   ret, addr);
+}
+
+static uint8_t
+sil164_read(struct i2c_client *client, uint8_t addr)
+{
+	uint8_t val;
+	int ret;
+
+	ret = i2c_master_send(client, &addr, sizeof(addr));
+	if (ret < 0)
+		goto fail;
+
+	ret = i2c_master_recv(client, &val, sizeof(val));
+	if (ret < 0)
+		goto fail;
+
+	return val;
+
+fail:
+	sil164_err(client, "Error %d reading from subaddress 0x%x\n",
+		   ret, addr);
+	return 0;
+}
+
+static void
+sil164_save_state(struct i2c_client *client, uint8_t *state)
+{
+	int i;
+
+	for (i = 0x8; i <= 0xe; i++)
+		state[i] = sil164_read(client, i);
+}
+
+static void
+sil164_restore_state(struct i2c_client *client, uint8_t *state)
+{
+	int i;
+
+	for (i = 0x8; i <= 0xe; i++)
+		sil164_write(client, i, state[i]);
+}
+
+static void
+sil164_set_power_state(struct i2c_client *client, bool on)
+{
+	uint8_t control0 = sil164_read(client, SIL164_CONTROL0);
+
+	if (on)
+		control0 |= SIL164_CONTROL0_POWER_ON;
+	else
+		control0 &= ~SIL164_CONTROL0_POWER_ON;
+
+	sil164_write(client, SIL164_CONTROL0, control0);
+}
+
+static void
+sil164_init_state(struct i2c_client *client,
+		  struct sil164_encoder_params *config,
+		  bool duallink)
+{
+	sil164_write(client, SIL164_CONTROL0,
+		     SIL164_CONTROL0_HSYNC_ON |
+		     SIL164_CONTROL0_VSYNC_ON |
+		     (config->input_edge ? SIL164_CONTROL0_EDGE_RISING : 0) |
+		     (config->input_width ? SIL164_CONTROL0_INPUT_24BIT : 0) |
+		     (config->input_dual ? SIL164_CONTROL0_DUAL_EDGE : 0));
+
+	sil164_write(client, SIL164_DETECT,
+		     SIL164_DETECT_INTR_STAT |
+		     SIL164_DETECT_OUT_MODE_RECEIVER);
+
+	sil164_write(client, SIL164_CONTROL1,
+		     (config->input_skew ? SIL164_CONTROL1_DESKEW_ENABLE : 0) |
+		     (((config->input_skew + 4) & 0x7)
+		      << SIL164_CONTROL1_DESKEW_INCR_SHIFT));
+
+	sil164_write(client, SIL164_CONTROL2,
+		     SIL164_CONTROL2_SYNC_CONT |
+		     (config->pll_filter ? 0 : SIL164_CONTROL2_FILTER_ENABLE) |
+		     (4 << SIL164_CONTROL2_FILTER_SETTING_SHIFT));
+
+	sil164_write(client, SIL164_PLLZONE, 0);
+
+	if (duallink)
+		sil164_write(client, SIL164_DUALLINK,
+			     SIL164_DUALLINK_ENABLE |
+			     (((config->duallink_skew + 4) & 0x7)
+			      << SIL164_DUALLINK_SKEW_SHIFT));
+	else
+		sil164_write(client, SIL164_DUALLINK, 0);
+}
+
+/* DRM encoder functions */
+
+static void
+sil164_encoder_set_config(struct drm_encoder *encoder, void *params)
+{
+	struct sil164_priv *priv = to_sil164_priv(encoder);
+
+	priv->config = *(struct sil164_encoder_params *)params;
+}
+
+static void
+sil164_encoder_dpms(struct drm_encoder *encoder, int mode)
+{
+	struct sil164_priv *priv = to_sil164_priv(encoder);
+	bool on = (mode == DRM_MODE_DPMS_ON);
+	bool duallink = (on && encoder->crtc->mode.clock > 165000);
+
+	sil164_set_power_state(drm_i2c_encoder_get_client(encoder), on);
+
+	if (priv->duallink_slave)
+		sil164_set_power_state(priv->duallink_slave, duallink);
+}
+
+static void
+sil164_encoder_save(struct drm_encoder *encoder)
+{
+	struct sil164_priv *priv = to_sil164_priv(encoder);
+
+	sil164_save_state(drm_i2c_encoder_get_client(encoder),
+			  priv->saved_state);
+
+	if (priv->duallink_slave)
+		sil164_save_state(priv->duallink_slave,
+				  priv->saved_slave_state);
+}
+
+static void
+sil164_encoder_restore(struct drm_encoder *encoder)
+{
+	struct sil164_priv *priv = to_sil164_priv(encoder);
+
+	sil164_restore_state(drm_i2c_encoder_get_client(encoder),
+			     priv->saved_state);
+
+	if (priv->duallink_slave)
+		sil164_restore_state(priv->duallink_slave,
+				     priv->saved_slave_state);
+}
+
+static bool
+sil164_encoder_mode_fixup(struct drm_encoder *encoder,
+			  struct drm_display_mode *mode,
+			  struct drm_display_mode *adjusted_mode)
+{
+	return true;
+}
+
+static int
+sil164_encoder_mode_valid(struct drm_encoder *encoder,
+			  struct drm_display_mode *mode)
+{
+	struct sil164_priv *priv = to_sil164_priv(encoder);
+
+	if (mode->clock < 32000)
+		return MODE_CLOCK_LOW;
+
+	if (mode->clock > 330000 ||
+	    (mode->clock > 165000 && !priv->duallink_slave))
+		return MODE_CLOCK_HIGH;
+
+	return MODE_OK;
+}
+
+static void
+sil164_encoder_mode_set(struct drm_encoder *encoder,
+			struct drm_display_mode *mode,
+			struct drm_display_mode *adjusted_mode)
+{
+	struct sil164_priv *priv = to_sil164_priv(encoder);
+	bool duallink = adjusted_mode->clock > 165000;
+
+	sil164_init_state(drm_i2c_encoder_get_client(encoder),
+			  &priv->config, duallink);
+
+	if (priv->duallink_slave)
+		sil164_init_state(priv->duallink_slave,
+				  &priv->config, duallink);
+
+	sil164_encoder_dpms(encoder, DRM_MODE_DPMS_ON);
+}
+
+static enum drm_connector_status
+sil164_encoder_detect(struct drm_encoder *encoder,
+		      struct drm_connector *connector)
+{
+	struct i2c_client *client = drm_i2c_encoder_get_client(encoder);
+
+	if (sil164_read(client, SIL164_DETECT) & SIL164_DETECT_HOTPLUG_STAT)
+		return connector_status_connected;
+	else
+		return connector_status_disconnected;
+}
+
+static int
+sil164_encoder_get_modes(struct drm_encoder *encoder,
+			 struct drm_connector *connector)
+{
+	return 0;
+}
+
+static int
+sil164_encoder_create_resources(struct drm_encoder *encoder,
+				struct drm_connector *connector)
+{
+	return 0;
+}
+
+static int
+sil164_encoder_set_property(struct drm_encoder *encoder,
+			    struct drm_connector *connector,
+			    struct drm_property *property,
+			    uint64_t val)
+{
+	return 0;
+}
+
+static void
+sil164_encoder_destroy(struct drm_encoder *encoder)
+{
+	struct sil164_priv *priv = to_sil164_priv(encoder);
+
+	if (priv->duallink_slave)
+		i2c_unregister_device(priv->duallink_slave);
+
+	kfree(priv);
+	drm_i2c_encoder_destroy(encoder);
+}
+
+static struct drm_encoder_slave_funcs sil164_encoder_funcs = {
+	.set_config = sil164_encoder_set_config,
+	.destroy = sil164_encoder_destroy,
+	.dpms = sil164_encoder_dpms,
+	.save = sil164_encoder_save,
+	.restore = sil164_encoder_restore,
+	.mode_fixup = sil164_encoder_mode_fixup,
+	.mode_valid = sil164_encoder_mode_valid,
+	.mode_set = sil164_encoder_mode_set,
+	.detect = sil164_encoder_detect,
+	.get_modes = sil164_encoder_get_modes,
+	.create_resources = sil164_encoder_create_resources,
+	.set_property = sil164_encoder_set_property,
+};
+
+/* I2C driver functions */
+
+static int
+sil164_probe(struct i2c_client *client, const struct i2c_device_id *id)
+{
+	int vendor = sil164_read(client, SIL164_VENDOR_HI) << 8 |
+		sil164_read(client, SIL164_VENDOR_LO);
+	int device = sil164_read(client, SIL164_DEVICE_HI) << 8 |
+		sil164_read(client, SIL164_DEVICE_LO);
+	int rev = sil164_read(client, SIL164_REVISION);
+
+	if (vendor != 0x1 || device != 0x6) {
+		sil164_dbg(client, "Unknown device %x:%x.%x\n",
+			   vendor, device, rev);
+		return -ENODEV;
+	}
+
+	sil164_info(client, "Detected device %x:%x.%x\n",
+		    vendor, device, rev);
+
+	return 0;
+}
+
+static int
+sil164_remove(struct i2c_client *client)
+{
+	return 0;
+}
+
+static struct i2c_client *
+sil164_detect_slave(struct i2c_client *client)
+{
+	struct i2c_adapter *adap = client->adapter;
+	struct i2c_msg msg = {
+		.addr = SIL164_I2C_ADDR_SLAVE,
+		.len = 0,
+	};
+	const struct i2c_board_info info = {
+		I2C_BOARD_INFO("sil164", SIL164_I2C_ADDR_SLAVE)
+	};
+
+	if (i2c_transfer(adap, &msg, 1) != 1) {
+		sil164_dbg(adap, "No dual-link slave found.");
+		return NULL;
+	}
+
+	return i2c_new_device(adap, &info);
+}
+
+static int
+sil164_encoder_init(struct i2c_client *client,
+		    struct drm_device *dev,
+		    struct drm_encoder_slave *encoder)
+{
+	struct sil164_priv *priv;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	encoder->slave_priv = priv;
+	encoder->slave_funcs = &sil164_encoder_funcs;
+
+	priv->duallink_slave = sil164_detect_slave(client);
+
+	return 0;
+}
+
+static struct i2c_device_id sil164_ids[] = {
+	{ "sil164", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, sil164_ids);
+
+static struct drm_i2c_encoder_driver sil164_driver = {
+	.i2c_driver = {
+		.probe = sil164_probe,
+		.remove = sil164_remove,
+		.driver = {
+			.name = "sil164",
+		},
+		.id_table = sil164_ids,
+	},
+	.encoder_init = sil164_encoder_init,
+};
+
+/* Module initialization */
+
+static int __init
+sil164_init(void)
+{
+	return drm_i2c_encoder_register(THIS_MODULE, &sil164_driver);
+}
+
+static void __exit
+sil164_exit(void)
+{
+	drm_i2c_encoder_unregister(&sil164_driver);
+}
+
+MODULE_AUTHOR("Francisco Jerez <currojerez@riseup.net>");
+MODULE_DESCRIPTION("Silicon Image sil164 TMDS transmitter driver");
+MODULE_LICENSE("GPL and additional rights");
+
+module_init(sil164_init);
+module_exit(sil164_exit);