drives/i2c/designware: incorporate device_operations support

In ramstage the device_operations are needed for the i2c designware
host controller. Move the intel/common/block/i2c implementation
into the generic driver so other platforms can take advantage of it.

BUG=b:72121803

Change-Id: Id249933fadcc016bfba00e7a6d65f56dfc220724
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/23372
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Subrata Banik <subrata.banik@intel.com>

src/drivers/i2c/designware/dw_i2c.c

@@ -19,10 +19,8 @@
 #include <arch/io.h>
 #include <console/console.h>
 #include <device/device.h>
+#include <device/i2c_bus.h>
 #include <device/i2c_simple.h>
-#include <device/pci.h>
-#include <device/pci_def.h>
-#include <device/pci_ids.h>
 #include <string.h>
 #include <timer.h>
 #include "dw_i2c.h"
@@ -726,3 +724,123 @@ int dw_i2c_init(unsigned int bus, const struct dw_i2c_bus_config *bcfg)
 
 	return 0;
 }
+
+/*
+ * Write ACPI object to describe speed configuration.
+ *
+ * ACPI Object: Name ("xxxx", Package () { scl_lcnt, scl_hcnt, sda_hold }
+ *
+ * SSCN: I2C_SPEED_STANDARD
+ * FMCN: I2C_SPEED_FAST
+ * FPCN: I2C_SPEED_FAST_PLUS
+ * HSCN: I2C_SPEED_HIGH
+ */
+static void dw_i2c_acpi_write_speed_config(
+	const struct dw_i2c_speed_config *config)
+{
+	if (!config)
+		return;
+	if (!config->scl_lcnt && !config->scl_hcnt && !config->sda_hold)
+		return;
+
+	if (config->speed >= I2C_SPEED_HIGH)
+		acpigen_write_name("HSCN");
+	else if (config->speed >= I2C_SPEED_FAST_PLUS)
+		acpigen_write_name("FPCN");
+	else if (config->speed >= I2C_SPEED_FAST)
+		acpigen_write_name("FMCN");
+	else
+		acpigen_write_name("SSCN");
+
+	/* Package () { scl_lcnt, scl_hcnt, sda_hold } */
+	acpigen_write_package(3);
+	acpigen_write_word(config->scl_hcnt);
+	acpigen_write_word(config->scl_lcnt);
+	acpigen_write_dword(config->sda_hold);
+	acpigen_pop_len();
+}
+
+/*
+ * The device should already be enabled and out of reset,
+ * either from early init in coreboot or SiliconInit in FSP.
+ */
+void dw_i2c_dev_init(struct device *dev)
+{
+	const struct dw_i2c_bus_config *config;
+	int bus = dw_i2c_soc_dev_to_bus(dev);
+
+	if (bus < 0)
+		return;
+
+	config = dw_i2c_get_soc_cfg(bus, dev);
+
+	if (!config)
+		return;
+
+	dw_i2c_init(bus, config);
+}
+
+/*
+ * Generate I2C timing information into the SSDT for the OS driver to consume,
+ * optionally applying override values provided by the caller.
+ */
+void dw_i2c_acpi_fill_ssdt(struct device *dev)
+{
+	const struct dw_i2c_bus_config *bcfg;
+	uintptr_t dw_i2c_addr;
+	struct dw_i2c_speed_config sgen;
+	enum i2c_speed speeds[DW_I2C_SPEED_CONFIG_COUNT] = {
+		I2C_SPEED_STANDARD,
+		I2C_SPEED_FAST,
+		I2C_SPEED_FAST_PLUS,
+		I2C_SPEED_HIGH,
+	};
+	int i, bus;
+	const char *path;
+
+	if (!dev->enabled)
+		return;
+
+	bus = dw_i2c_soc_dev_to_bus(dev);
+
+	if (bus < 0)
+		return;
+
+	bcfg = dw_i2c_get_soc_cfg(bus, dev);
+
+	if (!bcfg)
+		return;
+
+	dw_i2c_addr = dw_i2c_base_address(bus);
+	if (!dw_i2c_addr)
+		return;
+
+	path = acpi_device_path(dev);
+	if (!path)
+		return;
+
+	acpigen_write_scope(path);
+
+	/* Report timing values for the OS driver */
+	for (i = 0; i < DW_I2C_SPEED_CONFIG_COUNT; i++) {
+		/* Generate speed config. */
+		if (dw_i2c_gen_speed_config(dw_i2c_addr, speeds[i], bcfg,
+						&sgen) < 0)
+			continue;
+
+		/* Generate ACPI based on selected speed config */
+		dw_i2c_acpi_write_speed_config(&sgen);
+	}
+
+	acpigen_pop_len();
+}
+
+static int dw_i2c_dev_transfer(struct device *dev,
+				const struct i2c_msg *msg, size_t count)
+{
+	return dw_i2c_transfer(dw_i2c_soc_dev_to_bus(dev), msg, count);
+}
+
+const struct i2c_bus_operations dw_i2c_bus_ops = {
+	.transfer = dw_i2c_dev_transfer,
+};