mfd: Add cs5535-mfd driver for AMD Geode's CS5535/CS5536 support

Add an MFD driver to handle the ISA device on CS5535 and CS5536
southbridges. This ISA bridge is actually multiple devices: GPIOs,
MFGPTs, etc.

Signed-off-by: Andres Salomon <dilinger@queued.net>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

3 files changed, 160 insertions, 0 deletions

diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index da9d2971102e..b5e3e09f5637 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -537,6 +537,14 @@ config AB3550_CORE
           LEDs, vibrator, system power and temperature, power management
           and ALSA sound.
 
+config MFD_CS5535
+        tristate "Support for CS5535 and CS5536 southbridge core functions"
+        select MFD_CORE
+        depends on PCI
+        ---help---
+          This is the core driver for CS5535/CS5536 MFD functions.  This is
+          necessary for using the board's GPIO and MFGPT functionality.
+
 config MFD_TIMBERDALE
         tristate "Support for the Timberdale FPGA"
         select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 848e7eac75aa..5f35de9386e3 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -82,3 +82,4 @@ obj-$(CONFIG_MFD_JZ4740_ADC)	+= jz4740-adc.o
 obj-$(CONFIG_MFD_TPS6586X)      += tps6586x.o
 obj-$(CONFIG_MFD_VX855)         += vx855.o
 obj-$(CONFIG_MFD_WL1273_CORE)   += wl1273-core.o
+obj-$(CONFIG_MFD_CS5535)        += cs5535-mfd.o
diff --git a/drivers/mfd/cs5535-mfd.c b/drivers/mfd/cs5535-mfd.c
new file mode 100644
index 000000000000..b141ca7c777c
--- /dev/null
+++ b/drivers/mfd/cs5535-mfd.c
@@ -0,0 +1,151 @@
+/*
+ * cs5535-mfd.c - core MFD driver for CS5535/CS5536 southbridges
+ *
+ * The CS5535 and CS5536 has an ISA bridge on the PCI bus that is
+ * used for accessing GPIOs, MFGPTs, ACPI, etc.  Each subdevice has
+ * an IO range that's specified in a single BAR.  The BAR order is
+ * hardcoded in the CS553x specifications.
+ *
+ * Copyright (c) 2010  Andres Salomon <dilinger@queued.net>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/mfd/core.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+
+#define DRV_NAME "cs5535-mfd"
+
+enum cs5535_mfd_bars {
+        SMB_BAR = 0,
+        GPIO_BAR = 1,
+        MFGPT_BAR = 2,
+        PMS_BAR = 4,
+        ACPI_BAR = 5,
+        NR_BARS,
+};
+
+static __devinitdata struct resource cs5535_mfd_resources[NR_BARS];
+
+static __devinitdata struct mfd_cell cs5535_mfd_cells[] = {
+        {
+                .id = SMB_BAR,
+                .name = "cs5535-smb",
+                .num_resources = 1,
+                .resources = &cs5535_mfd_resources[SMB_BAR],
+        },
+        {
+                .id = GPIO_BAR,
+                .name = "cs5535-gpio",
+                .num_resources = 1,
+                .resources = &cs5535_mfd_resources[GPIO_BAR],
+        },
+        {
+                .id = MFGPT_BAR,
+                .name = "cs5535-mfgpt",
+                .num_resources = 1,
+                .resources = &cs5535_mfd_resources[MFGPT_BAR],
+        },
+        {
+                .id = PMS_BAR,
+                .name = "cs5535-pms",
+                .num_resources = 1,
+                .resources = &cs5535_mfd_resources[PMS_BAR],
+        },
+        {
+                .id = ACPI_BAR,
+                .name = "cs5535-acpi",
+                .num_resources = 1,
+                .resources = &cs5535_mfd_resources[ACPI_BAR],
+        },
+};
+
+static int __devinit cs5535_mfd_probe(struct pci_dev *pdev,
+                const struct pci_device_id *id)
+{
+        int err, i;
+
+        err = pci_enable_device(pdev);
+        if (err)
+                return err;
+
+        /* fill in IO range for each cell; subdrivers handle the region */
+        for (i = 0; i < ARRAY_SIZE(cs5535_mfd_cells); i++) {
+                int bar = cs5535_mfd_cells[i].id;
+                struct resource *r = &cs5535_mfd_resources[bar];
+
+                r->flags = IORESOURCE_IO;
+                r->start = pci_resource_start(pdev, bar);
+                r->end = pci_resource_end(pdev, bar);
+
+                /* id is used for temporarily storing BAR; unset it now */
+                cs5535_mfd_cells[i].id = 0;
+        }
+
+        err = mfd_add_devices(&pdev->dev, -1, cs5535_mfd_cells,
+                        ARRAY_SIZE(cs5535_mfd_cells), NULL, 0);
+        if (err) {
+                dev_err(&pdev->dev, "MFD add devices failed: %d\n", err);
+                goto err_disable;
+        }
+
+        dev_info(&pdev->dev, "%d devices registered.\n",
+                        ARRAY_SIZE(cs5535_mfd_cells));
+
+        return 0;
+
+err_disable:
+        pci_disable_device(pdev);
+        return err;
+}
+
+static void __devexit cs5535_mfd_remove(struct pci_dev *pdev)
+{
+        mfd_remove_devices(&pdev->dev);
+        pci_disable_device(pdev);
+}
+
+static struct pci_device_id cs5535_mfd_pci_tbl[] = {
+        { PCI_DEVICE(PCI_VENDOR_ID_NS, PCI_DEVICE_ID_NS_CS5535_ISA) },
+        { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_CS5536_ISA) },
+        { 0, }
+};
+MODULE_DEVICE_TABLE(pci, cs5535_mfd_pci_tbl);
+
+static struct pci_driver cs5535_mfd_drv = {
+        .name = DRV_NAME,
+        .id_table = cs5535_mfd_pci_tbl,
+        .probe = cs5535_mfd_probe,
+        .remove = __devexit_p(cs5535_mfd_remove),
+};
+
+static int __init cs5535_mfd_init(void)
+{
+        return pci_register_driver(&cs5535_mfd_drv);
+}
+
+static void __exit cs5535_mfd_exit(void)
+{
+        pci_unregister_driver(&cs5535_mfd_drv);
+}
+
+module_init(cs5535_mfd_init);
+module_exit(cs5535_mfd_exit);
+
+MODULE_AUTHOR("Andres Salomon <dilinger@queued.net>");
+MODULE_DESCRIPTION("MFD driver for CS5535/CS5536 southbridge's ISA PCI device");
+MODULE_LICENSE("GPL");