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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/mfd/sta2x11-mfd.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/mfd/sta2x11-mfd.c')
-rw-r--r--drivers/mfd/sta2x11-mfd.c645
1 files changed, 645 insertions, 0 deletions
diff --git a/drivers/mfd/sta2x11-mfd.c b/drivers/mfd/sta2x11-mfd.c
new file mode 100644
index 000000000..02cc49daf
--- /dev/null
+++ b/drivers/mfd/sta2x11-mfd.c
@@ -0,0 +1,645 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * STA2x11 mfd for GPIO, SCTL and APBREG
+ *
+ * Copyright (c) 2009-2011 Wind River Systems, Inc.
+ * Copyright (c) 2011 ST Microelectronics (Alessandro Rubini, Davide Ciminaghi)
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/export.h>
+#include <linux/spinlock.h>
+#include <linux/errno.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/list.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/pci.h>
+#include <linux/seq_file.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/core.h>
+#include <linux/mfd/sta2x11-mfd.h>
+#include <linux/regmap.h>
+
+#include <asm/sta2x11.h>
+
+static inline int __reg_within_range(unsigned int r,
+ unsigned int start,
+ unsigned int end)
+{
+ return ((r >= start) && (r <= end));
+}
+
+/* This describes STA2X11 MFD chip for us, we may have several */
+struct sta2x11_mfd {
+ struct sta2x11_instance *instance;
+ struct regmap *regmap[sta2x11_n_mfd_plat_devs];
+ spinlock_t lock[sta2x11_n_mfd_plat_devs];
+ struct list_head list;
+ void __iomem *regs[sta2x11_n_mfd_plat_devs];
+};
+
+static LIST_HEAD(sta2x11_mfd_list);
+
+/* Three functions to act on the list */
+static struct sta2x11_mfd *sta2x11_mfd_find(struct pci_dev *pdev)
+{
+ struct sta2x11_instance *instance;
+ struct sta2x11_mfd *mfd;
+
+ if (!pdev && !list_empty(&sta2x11_mfd_list)) {
+ pr_warn("%s: Unspecified device, using first instance\n",
+ __func__);
+ return list_entry(sta2x11_mfd_list.next,
+ struct sta2x11_mfd, list);
+ }
+
+ instance = sta2x11_get_instance(pdev);
+ if (!instance)
+ return NULL;
+ list_for_each_entry(mfd, &sta2x11_mfd_list, list) {
+ if (mfd->instance == instance)
+ return mfd;
+ }
+ return NULL;
+}
+
+static int sta2x11_mfd_add(struct pci_dev *pdev, gfp_t flags)
+{
+ int i;
+ struct sta2x11_mfd *mfd = sta2x11_mfd_find(pdev);
+ struct sta2x11_instance *instance;
+
+ if (mfd)
+ return -EBUSY;
+ instance = sta2x11_get_instance(pdev);
+ if (!instance)
+ return -EINVAL;
+ mfd = kzalloc(sizeof(*mfd), flags);
+ if (!mfd)
+ return -ENOMEM;
+ INIT_LIST_HEAD(&mfd->list);
+ for (i = 0; i < ARRAY_SIZE(mfd->lock); i++)
+ spin_lock_init(&mfd->lock[i]);
+ mfd->instance = instance;
+ list_add(&mfd->list, &sta2x11_mfd_list);
+ return 0;
+}
+
+/* This function is exported and is not expected to fail */
+u32 __sta2x11_mfd_mask(struct pci_dev *pdev, u32 reg, u32 mask, u32 val,
+ enum sta2x11_mfd_plat_dev index)
+{
+ struct sta2x11_mfd *mfd = sta2x11_mfd_find(pdev);
+ u32 r;
+ unsigned long flags;
+ void __iomem *regs;
+
+ if (!mfd) {
+ dev_warn(&pdev->dev, ": can't access sctl regs\n");
+ return 0;
+ }
+
+ regs = mfd->regs[index];
+ if (!regs) {
+ dev_warn(&pdev->dev, ": system ctl not initialized\n");
+ return 0;
+ }
+ spin_lock_irqsave(&mfd->lock[index], flags);
+ r = readl(regs + reg);
+ r &= ~mask;
+ r |= val;
+ if (mask)
+ writel(r, regs + reg);
+ spin_unlock_irqrestore(&mfd->lock[index], flags);
+ return r;
+}
+EXPORT_SYMBOL(__sta2x11_mfd_mask);
+
+int sta2x11_mfd_get_regs_data(struct platform_device *dev,
+ enum sta2x11_mfd_plat_dev index,
+ void __iomem **regs,
+ spinlock_t **lock)
+{
+ struct pci_dev *pdev = *(struct pci_dev **)dev_get_platdata(&dev->dev);
+ struct sta2x11_mfd *mfd;
+
+ if (!pdev)
+ return -ENODEV;
+ mfd = sta2x11_mfd_find(pdev);
+ if (!mfd)
+ return -ENODEV;
+ if (index >= sta2x11_n_mfd_plat_devs)
+ return -ENODEV;
+ *regs = mfd->regs[index];
+ *lock = &mfd->lock[index];
+ pr_debug("%s %d *regs = %p\n", __func__, __LINE__, *regs);
+ return *regs ? 0 : -ENODEV;
+}
+EXPORT_SYMBOL(sta2x11_mfd_get_regs_data);
+
+/*
+ * Special sta2x11-mfd regmap lock/unlock functions
+ */
+
+static void sta2x11_regmap_lock(void *__lock)
+{
+ spinlock_t *lock = __lock;
+ spin_lock(lock);
+}
+
+static void sta2x11_regmap_unlock(void *__lock)
+{
+ spinlock_t *lock = __lock;
+ spin_unlock(lock);
+}
+
+/* OTP (one time programmable registers do not require locking */
+static void sta2x11_regmap_nolock(void *__lock)
+{
+}
+
+static const char *sta2x11_mfd_names[sta2x11_n_mfd_plat_devs] = {
+ [sta2x11_sctl] = STA2X11_MFD_SCTL_NAME,
+ [sta2x11_apbreg] = STA2X11_MFD_APBREG_NAME,
+ [sta2x11_apb_soc_regs] = STA2X11_MFD_APB_SOC_REGS_NAME,
+ [sta2x11_scr] = STA2X11_MFD_SCR_NAME,
+};
+
+static bool sta2x11_sctl_writeable_reg(struct device *dev, unsigned int reg)
+{
+ return !__reg_within_range(reg, SCTL_SCPCIECSBRST, SCTL_SCRSTSTA);
+}
+
+static struct regmap_config sta2x11_sctl_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .lock = sta2x11_regmap_lock,
+ .unlock = sta2x11_regmap_unlock,
+ .max_register = SCTL_SCRSTSTA,
+ .writeable_reg = sta2x11_sctl_writeable_reg,
+};
+
+static bool sta2x11_scr_readable_reg(struct device *dev, unsigned int reg)
+{
+ return (reg == STA2X11_SECR_CR) ||
+ __reg_within_range(reg, STA2X11_SECR_FVR0, STA2X11_SECR_FVR1);
+}
+
+static bool sta2x11_scr_writeable_reg(struct device *dev, unsigned int reg)
+{
+ return false;
+}
+
+static struct regmap_config sta2x11_scr_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .lock = sta2x11_regmap_nolock,
+ .unlock = sta2x11_regmap_nolock,
+ .max_register = STA2X11_SECR_FVR1,
+ .readable_reg = sta2x11_scr_readable_reg,
+ .writeable_reg = sta2x11_scr_writeable_reg,
+};
+
+static bool sta2x11_apbreg_readable_reg(struct device *dev, unsigned int reg)
+{
+ /* Two blocks (CAN and MLB, SARAC) 0x100 bytes apart */
+ if (reg >= APBREG_BSR_SARAC)
+ reg -= APBREG_BSR_SARAC;
+ switch (reg) {
+ case APBREG_BSR:
+ case APBREG_PAER:
+ case APBREG_PWAC:
+ case APBREG_PRAC:
+ case APBREG_PCG:
+ case APBREG_PUR:
+ case APBREG_EMU_PCG:
+ return true;
+ default:
+ return false;
+ }
+}
+
+static bool sta2x11_apbreg_writeable_reg(struct device *dev, unsigned int reg)
+{
+ if (reg >= APBREG_BSR_SARAC)
+ reg -= APBREG_BSR_SARAC;
+ if (!sta2x11_apbreg_readable_reg(dev, reg))
+ return false;
+ return reg != APBREG_PAER;
+}
+
+static struct regmap_config sta2x11_apbreg_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .lock = sta2x11_regmap_lock,
+ .unlock = sta2x11_regmap_unlock,
+ .max_register = APBREG_EMU_PCG_SARAC,
+ .readable_reg = sta2x11_apbreg_readable_reg,
+ .writeable_reg = sta2x11_apbreg_writeable_reg,
+};
+
+static bool sta2x11_apb_soc_regs_readable_reg(struct device *dev,
+ unsigned int reg)
+{
+ return reg <= PCIE_SoC_INT_ROUTER_STATUS3_REG ||
+ __reg_within_range(reg, DMA_IP_CTRL_REG, SPARE3_RESERVED) ||
+ __reg_within_range(reg, MASTER_LOCK_REG,
+ SYSTEM_CONFIG_STATUS_REG) ||
+ reg == MSP_CLK_CTRL_REG ||
+ __reg_within_range(reg, COMPENSATION_REG1, TEST_CTL_REG);
+}
+
+static bool sta2x11_apb_soc_regs_writeable_reg(struct device *dev,
+ unsigned int reg)
+{
+ if (!sta2x11_apb_soc_regs_readable_reg(dev, reg))
+ return false;
+ switch (reg) {
+ case PCIE_COMMON_CLOCK_CONFIG_0_4_0:
+ case SYSTEM_CONFIG_STATUS_REG:
+ case COMPENSATION_REG1:
+ case PCIE_SoC_INT_ROUTER_STATUS0_REG...PCIE_SoC_INT_ROUTER_STATUS3_REG:
+ case PCIE_PM_STATUS_0_PORT_0_4...PCIE_PM_STATUS_7_0_EP4:
+ return false;
+ default:
+ return true;
+ }
+}
+
+static struct regmap_config sta2x11_apb_soc_regs_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .lock = sta2x11_regmap_lock,
+ .unlock = sta2x11_regmap_unlock,
+ .max_register = TEST_CTL_REG,
+ .readable_reg = sta2x11_apb_soc_regs_readable_reg,
+ .writeable_reg = sta2x11_apb_soc_regs_writeable_reg,
+};
+
+static struct regmap_config *
+sta2x11_mfd_regmap_configs[sta2x11_n_mfd_plat_devs] = {
+ [sta2x11_sctl] = &sta2x11_sctl_regmap_config,
+ [sta2x11_apbreg] = &sta2x11_apbreg_regmap_config,
+ [sta2x11_apb_soc_regs] = &sta2x11_apb_soc_regs_regmap_config,
+ [sta2x11_scr] = &sta2x11_scr_regmap_config,
+};
+
+/* Probe for the four platform devices */
+
+static int sta2x11_mfd_platform_probe(struct platform_device *dev,
+ enum sta2x11_mfd_plat_dev index)
+{
+ struct pci_dev **pdev;
+ struct sta2x11_mfd *mfd;
+ struct resource *res;
+ const char *name = sta2x11_mfd_names[index];
+ struct regmap_config *regmap_config = sta2x11_mfd_regmap_configs[index];
+
+ pdev = dev_get_platdata(&dev->dev);
+ mfd = sta2x11_mfd_find(*pdev);
+ if (!mfd)
+ return -ENODEV;
+ if (!regmap_config)
+ return -ENODEV;
+
+ res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENOMEM;
+
+ if (!request_mem_region(res->start, resource_size(res), name))
+ return -EBUSY;
+
+ mfd->regs[index] = ioremap(res->start, resource_size(res));
+ if (!mfd->regs[index]) {
+ release_mem_region(res->start, resource_size(res));
+ return -ENOMEM;
+ }
+ regmap_config->lock_arg = &mfd->lock;
+ /*
+ No caching, registers could be reached both via regmap and via
+ void __iomem *
+ */
+ regmap_config->cache_type = REGCACHE_NONE;
+ mfd->regmap[index] = devm_regmap_init_mmio(&dev->dev, mfd->regs[index],
+ regmap_config);
+ WARN_ON(IS_ERR(mfd->regmap[index]));
+
+ return 0;
+}
+
+static int sta2x11_sctl_probe(struct platform_device *dev)
+{
+ return sta2x11_mfd_platform_probe(dev, sta2x11_sctl);
+}
+
+static int sta2x11_apbreg_probe(struct platform_device *dev)
+{
+ return sta2x11_mfd_platform_probe(dev, sta2x11_apbreg);
+}
+
+static int sta2x11_apb_soc_regs_probe(struct platform_device *dev)
+{
+ return sta2x11_mfd_platform_probe(dev, sta2x11_apb_soc_regs);
+}
+
+static int sta2x11_scr_probe(struct platform_device *dev)
+{
+ return sta2x11_mfd_platform_probe(dev, sta2x11_scr);
+}
+
+/* The three platform drivers */
+static struct platform_driver sta2x11_sctl_platform_driver = {
+ .driver = {
+ .name = STA2X11_MFD_SCTL_NAME,
+ },
+ .probe = sta2x11_sctl_probe,
+};
+
+static struct platform_driver sta2x11_platform_driver = {
+ .driver = {
+ .name = STA2X11_MFD_APBREG_NAME,
+ },
+ .probe = sta2x11_apbreg_probe,
+};
+
+static struct platform_driver sta2x11_apb_soc_regs_platform_driver = {
+ .driver = {
+ .name = STA2X11_MFD_APB_SOC_REGS_NAME,
+ },
+ .probe = sta2x11_apb_soc_regs_probe,
+};
+
+static struct platform_driver sta2x11_scr_platform_driver = {
+ .driver = {
+ .name = STA2X11_MFD_SCR_NAME,
+ },
+ .probe = sta2x11_scr_probe,
+};
+
+static struct platform_driver * const drivers[] = {
+ &sta2x11_platform_driver,
+ &sta2x11_sctl_platform_driver,
+ &sta2x11_apb_soc_regs_platform_driver,
+ &sta2x11_scr_platform_driver,
+};
+
+static int __init sta2x11_drivers_init(void)
+{
+ return platform_register_drivers(drivers, ARRAY_SIZE(drivers));
+}
+
+/*
+ * What follows are the PCI devices that host the above pdevs.
+ * Each logic block is 4kB and they are all consecutive: we use this info.
+ */
+
+/* Mfd 0 device */
+
+/* Mfd 0, Bar 0 */
+enum mfd0_bar0_cells {
+ STA2X11_GPIO_0 = 0,
+ STA2X11_GPIO_1,
+ STA2X11_GPIO_2,
+ STA2X11_GPIO_3,
+ STA2X11_SCTL,
+ STA2X11_SCR,
+ STA2X11_TIME,
+};
+/* Mfd 0 , Bar 1 */
+enum mfd0_bar1_cells {
+ STA2X11_APBREG = 0,
+};
+#define CELL_4K(_name, _cell) { \
+ .name = _name, \
+ .start = _cell * 4096, .end = _cell * 4096 + 4095, \
+ .flags = IORESOURCE_MEM, \
+ }
+
+static const struct resource gpio_resources[] = {
+ {
+ /* 4 consecutive cells, 1 driver */
+ .name = STA2X11_MFD_GPIO_NAME,
+ .start = 0,
+ .end = (4 * 4096) - 1,
+ .flags = IORESOURCE_MEM,
+ }
+};
+static const struct resource sctl_resources[] = {
+ CELL_4K(STA2X11_MFD_SCTL_NAME, STA2X11_SCTL),
+};
+static const struct resource scr_resources[] = {
+ CELL_4K(STA2X11_MFD_SCR_NAME, STA2X11_SCR),
+};
+static const struct resource time_resources[] = {
+ CELL_4K(STA2X11_MFD_TIME_NAME, STA2X11_TIME),
+};
+
+static const struct resource apbreg_resources[] = {
+ CELL_4K(STA2X11_MFD_APBREG_NAME, STA2X11_APBREG),
+};
+
+#define DEV(_name, _r) \
+ { .name = _name, .num_resources = ARRAY_SIZE(_r), .resources = _r, }
+
+static struct mfd_cell sta2x11_mfd0_bar0[] = {
+ /* offset 0: we add pdata later */
+ DEV(STA2X11_MFD_GPIO_NAME, gpio_resources),
+ DEV(STA2X11_MFD_SCTL_NAME, sctl_resources),
+ DEV(STA2X11_MFD_SCR_NAME, scr_resources),
+ DEV(STA2X11_MFD_TIME_NAME, time_resources),
+};
+
+static struct mfd_cell sta2x11_mfd0_bar1[] = {
+ DEV(STA2X11_MFD_APBREG_NAME, apbreg_resources),
+};
+
+/* Mfd 1 devices */
+
+/* Mfd 1, Bar 0 */
+enum mfd1_bar0_cells {
+ STA2X11_VIC = 0,
+};
+
+/* Mfd 1, Bar 1 */
+enum mfd1_bar1_cells {
+ STA2X11_APB_SOC_REGS = 0,
+};
+
+static const struct resource vic_resources[] = {
+ CELL_4K(STA2X11_MFD_VIC_NAME, STA2X11_VIC),
+};
+
+static const struct resource apb_soc_regs_resources[] = {
+ CELL_4K(STA2X11_MFD_APB_SOC_REGS_NAME, STA2X11_APB_SOC_REGS),
+};
+
+static struct mfd_cell sta2x11_mfd1_bar0[] = {
+ DEV(STA2X11_MFD_VIC_NAME, vic_resources),
+};
+
+static struct mfd_cell sta2x11_mfd1_bar1[] = {
+ DEV(STA2X11_MFD_APB_SOC_REGS_NAME, apb_soc_regs_resources),
+};
+
+
+static int sta2x11_mfd_suspend(struct pci_dev *pdev, pm_message_t state)
+{
+ pci_save_state(pdev);
+ pci_disable_device(pdev);
+ pci_set_power_state(pdev, pci_choose_state(pdev, state));
+
+ return 0;
+}
+
+static int sta2x11_mfd_resume(struct pci_dev *pdev)
+{
+ int err;
+
+ pci_set_power_state(pdev, PCI_D0);
+ err = pci_enable_device(pdev);
+ if (err)
+ return err;
+ pci_restore_state(pdev);
+
+ return 0;
+}
+
+struct sta2x11_mfd_bar_setup_data {
+ struct mfd_cell *cells;
+ int ncells;
+};
+
+struct sta2x11_mfd_setup_data {
+ struct sta2x11_mfd_bar_setup_data bars[2];
+};
+
+#define STA2X11_MFD0 0
+#define STA2X11_MFD1 1
+
+static struct sta2x11_mfd_setup_data mfd_setup_data[] = {
+ /* Mfd 0: gpio, sctl, scr, timers / apbregs */
+ [STA2X11_MFD0] = {
+ .bars = {
+ [0] = {
+ .cells = sta2x11_mfd0_bar0,
+ .ncells = ARRAY_SIZE(sta2x11_mfd0_bar0),
+ },
+ [1] = {
+ .cells = sta2x11_mfd0_bar1,
+ .ncells = ARRAY_SIZE(sta2x11_mfd0_bar1),
+ },
+ },
+ },
+ /* Mfd 1: vic / apb-soc-regs */
+ [STA2X11_MFD1] = {
+ .bars = {
+ [0] = {
+ .cells = sta2x11_mfd1_bar0,
+ .ncells = ARRAY_SIZE(sta2x11_mfd1_bar0),
+ },
+ [1] = {
+ .cells = sta2x11_mfd1_bar1,
+ .ncells = ARRAY_SIZE(sta2x11_mfd1_bar1),
+ },
+ },
+ },
+};
+
+static void sta2x11_mfd_setup(struct pci_dev *pdev,
+ struct sta2x11_mfd_setup_data *sd)
+{
+ int i, j;
+ for (i = 0; i < ARRAY_SIZE(sd->bars); i++)
+ for (j = 0; j < sd->bars[i].ncells; j++) {
+ sd->bars[i].cells[j].pdata_size = sizeof(pdev);
+ sd->bars[i].cells[j].platform_data = &pdev;
+ }
+}
+
+static int sta2x11_mfd_probe(struct pci_dev *pdev,
+ const struct pci_device_id *pci_id)
+{
+ int err, i;
+ struct sta2x11_mfd_setup_data *setup_data;
+
+ dev_info(&pdev->dev, "%s\n", __func__);
+
+ err = pci_enable_device(pdev);
+ if (err) {
+ dev_err(&pdev->dev, "Can't enable device.\n");
+ return err;
+ }
+
+ err = pci_enable_msi(pdev);
+ if (err)
+ dev_info(&pdev->dev, "Enable msi failed\n");
+
+ setup_data = pci_id->device == PCI_DEVICE_ID_STMICRO_GPIO ?
+ &mfd_setup_data[STA2X11_MFD0] :
+ &mfd_setup_data[STA2X11_MFD1];
+
+ /* platform data is the pci device for all of them */
+ sta2x11_mfd_setup(pdev, setup_data);
+
+ /* Record this pdev before mfd_add_devices: their probe looks for it */
+ if (!sta2x11_mfd_find(pdev))
+ sta2x11_mfd_add(pdev, GFP_KERNEL);
+
+ /* Just 2 bars for all mfd's at present */
+ for (i = 0; i < 2; i++) {
+ err = mfd_add_devices(&pdev->dev, -1,
+ setup_data->bars[i].cells,
+ setup_data->bars[i].ncells,
+ &pdev->resource[i],
+ 0, NULL);
+ if (err) {
+ dev_err(&pdev->dev,
+ "mfd_add_devices[%d] failed: %d\n", i, err);
+ goto err_disable;
+ }
+ }
+
+ return 0;
+
+err_disable:
+ mfd_remove_devices(&pdev->dev);
+ pci_disable_device(pdev);
+ pci_disable_msi(pdev);
+ return err;
+}
+
+static const struct pci_device_id sta2x11_mfd_tbl[] = {
+ {PCI_DEVICE(PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_GPIO)},
+ {PCI_DEVICE(PCI_VENDOR_ID_STMICRO, PCI_DEVICE_ID_STMICRO_VIC)},
+ {0,},
+};
+
+static struct pci_driver sta2x11_mfd_driver = {
+ .name = "sta2x11-mfd",
+ .id_table = sta2x11_mfd_tbl,
+ .probe = sta2x11_mfd_probe,
+ .suspend = sta2x11_mfd_suspend,
+ .resume = sta2x11_mfd_resume,
+};
+
+static int __init sta2x11_mfd_init(void)
+{
+ pr_info("%s\n", __func__);
+ return pci_register_driver(&sta2x11_mfd_driver);
+}
+
+/*
+ * All of this must be ready before "normal" devices like MMCI appear.
+ * But MFD (the pci device) can't be too early. The following choice
+ * prepares platform drivers very early and probe the PCI device later,
+ * but before other PCI devices.
+ */
+subsys_initcall(sta2x11_drivers_init);
+rootfs_initcall(sta2x11_mfd_init);