mfd: intel-m10-bmc: Split into core and spi specific parts

Split the common code from intel-m10-bmc driver into intel-m10-bmc-core
and move the SPI bus parts into an interface specific file.

intel-m10-bmc-core becomes the core MFD functions which can support
multiple bus interface like SPI bus.

Co-developed-by: Tianfei zhang <tianfei.zhang@intel.com>
Signed-off-by: Tianfei zhang <tianfei.zhang@intel.com>
Reviewed-by: Russ Weight <russell.h.weight@intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net> # hwmon
Reviewed-by: Xu Yilun <yilun.xu@intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Lee Jones <lee@kernel.org>
Link: https://lore.kernel.org/r/20230116100845.6153-5-ilpo.jarvinen@linux.intel.com

1 files changed, 145 insertions, 0 deletions

diff --git a/drivers/mfd/intel-m10-bmc-spi.c b/drivers/mfd/intel-m10-bmc-spi.c
new file mode 100644
index 000000000000..be1d4ddedabb
--- /dev/null
+++ b/drivers/mfd/intel-m10-bmc-spi.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Intel MAX 10 Board Management Controller chip
+ *
+ * Copyright (C) 2018-2020 Intel Corporation. All rights reserved.
+ */
+#include <linux/bitfield.h>
+#include <linux/dev_printk.h>
+#include <linux/init.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/intel-m10-bmc.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/spi/spi.h>
+
+static const struct regmap_range m10bmc_regmap_range[] = {
+	regmap_reg_range(M10BMC_LEGACY_BUILD_VER, M10BMC_LEGACY_BUILD_VER),
+	regmap_reg_range(M10BMC_SYS_BASE, M10BMC_SYS_END),
+	regmap_reg_range(M10BMC_FLASH_BASE, M10BMC_FLASH_END),
+};
+
+static const struct regmap_access_table m10bmc_access_table = {
+	.yes_ranges	= m10bmc_regmap_range,
+	.n_yes_ranges	= ARRAY_SIZE(m10bmc_regmap_range),
+};
+
+static struct regmap_config intel_m10bmc_regmap_config = {
+	.reg_bits = 32,
+	.val_bits = 32,
+	.reg_stride = 4,
+	.wr_table = &m10bmc_access_table,
+	.rd_table = &m10bmc_access_table,
+	.max_register = M10BMC_MEM_END,
+};
+
+static int check_m10bmc_version(struct intel_m10bmc *ddata)
+{
+	unsigned int v;
+	int ret;
+
+	/*
+	 * This check is to filter out the very old legacy BMC versions. In the
+	 * old BMC chips, the BMC version info is stored in the old version
+	 * register (M10BMC_LEGACY_BUILD_VER), so its read out value would have
+	 * not been M10BMC_VER_LEGACY_INVALID (0xffffffff). But in new BMC
+	 * chips that the driver supports, the value of this register should be
+	 * M10BMC_VER_LEGACY_INVALID.
+	 */
+	ret = m10bmc_raw_read(ddata, M10BMC_LEGACY_BUILD_VER, &v);
+	if (ret)
+		return -ENODEV;
+
+	if (v != M10BMC_VER_LEGACY_INVALID) {
+		dev_err(ddata->dev, "bad version M10BMC detected\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static int intel_m10_bmc_spi_probe(struct spi_device *spi)
+{
+	const struct spi_device_id *id = spi_get_device_id(spi);
+	const struct intel_m10bmc_platform_info *info;
+	struct device *dev = &spi->dev;
+	struct intel_m10bmc *ddata;
+	int ret;
+
+	ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
+	if (!ddata)
+		return -ENOMEM;
+
+	info = (struct intel_m10bmc_platform_info *)id->driver_data;
+	ddata->dev = dev;
+
+	ddata->regmap = devm_regmap_init_spi_avmm(spi, &intel_m10bmc_regmap_config);
+	if (IS_ERR(ddata->regmap)) {
+		ret = PTR_ERR(ddata->regmap);
+		dev_err(dev, "Failed to allocate regmap: %d\n", ret);
+		return ret;
+	}
+
+	spi_set_drvdata(spi, ddata);
+
+	ret = check_m10bmc_version(ddata);
+	if (ret) {
+		dev_err(dev, "Failed to identify m10bmc hardware\n");
+		return ret;
+	}
+
+	return m10bmc_dev_init(ddata, info);
+}
+
+static struct mfd_cell m10bmc_d5005_subdevs[] = {
+	{ .name = "d5005bmc-hwmon" },
+	{ .name = "d5005bmc-sec-update" },
+};
+
+static struct mfd_cell m10bmc_pacn3000_subdevs[] = {
+	{ .name = "n3000bmc-hwmon" },
+	{ .name = "n3000bmc-retimer" },
+	{ .name = "n3000bmc-sec-update" },
+};
+
+static struct mfd_cell m10bmc_n5010_subdevs[] = {
+	{ .name = "n5010bmc-hwmon" },
+};
+
+static const struct intel_m10bmc_platform_info m10bmc_spi_n3000 = {
+	.cells = m10bmc_pacn3000_subdevs,
+	.n_cells = ARRAY_SIZE(m10bmc_pacn3000_subdevs),
+};
+
+static const struct intel_m10bmc_platform_info m10bmc_spi_d5005 = {
+	.cells = m10bmc_d5005_subdevs,
+	.n_cells = ARRAY_SIZE(m10bmc_d5005_subdevs),
+};
+
+static const struct intel_m10bmc_platform_info m10bmc_spi_n5010 = {
+	.cells = m10bmc_n5010_subdevs,
+	.n_cells = ARRAY_SIZE(m10bmc_n5010_subdevs),
+};
+
+static const struct spi_device_id m10bmc_spi_id[] = {
+	{ "m10-n3000", (kernel_ulong_t)&m10bmc_spi_n3000 },
+	{ "m10-d5005", (kernel_ulong_t)&m10bmc_spi_d5005 },
+	{ "m10-n5010", (kernel_ulong_t)&m10bmc_spi_n5010 },
+	{ }
+};
+MODULE_DEVICE_TABLE(spi, m10bmc_spi_id);
+
+static struct spi_driver intel_m10bmc_spi_driver = {
+	.driver = {
+		.name = "intel-m10-bmc",
+		.dev_groups = m10bmc_dev_groups,
+	},
+	.probe = intel_m10_bmc_spi_probe,
+	.id_table = m10bmc_spi_id,
+};
+module_spi_driver(intel_m10bmc_spi_driver);
+
+MODULE_DESCRIPTION("Intel MAX 10 BMC SPI bus interface");
+MODULE_AUTHOR("Intel Corporation");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("spi:intel-m10-bmc");