Dear Jim,
Thank you for the patch.
Am 20.12.22 um 09:01 schrieb Jim Liu:
Add Nuvoton BMC NPCM7xx sgpio driver support.
Please mention the datasheet, and how this is tested.
Signed-off-by: Jim Liu <JJLIU0@xxxxxxxxxxx>
The email address does not match the address the patch was sent from.
From the manual page git-send-email(1):
--from=<address>
Specify the sender of the emails. If not specified on the command
line, the value of the sendemail.from configuration option is used.
If neither the command-line option nor sendemail.from are set, then
the user will be prompted for the value. The default for the prompt
will be the value of GIT_AUTHOR_IDENT, or GIT_COMMITTER_IDENT if
that is not set, as returned by "git var -l".
(To avoid having to press the shift key, lowercase local part would be
nice: jjliu0@xxxxxxxxxxx. Depends on the server configuration though, if
it’s the same address.)
---
Changes for v3:
- remove return in bank_reg function
Changes for v2:
- add prefix
- write the enum values in all capitals
- remove _init in npcm_sgpio_probe
---
drivers/gpio/Kconfig | 8 +
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-npcm-sgpio.c | 639 +++++++++++++++++++++++++++++++++
3 files changed, 648 insertions(+)
create mode 100644 drivers/gpio/gpio-npcm-sgpio.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index ec7cfd4f52b1..c23fff243461 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -470,6 +470,14 @@ config GPIO_MXS
select GPIO_GENERIC
select GENERIC_IRQ_CHIP
+config GPIO_NPCM_SGPIO
+ bool "Nuvoton SGPIO support"
+ depends on (ARCH_NPCM || COMPILE_TEST) && OF_GPIO
+ select GPIO_GENERIC
+ select GPIOLIB_IRQCHIP
+ help
+ Say Y here to support Nuvoton NPCM7XX/NPCM8XX SGPIO functionality.
+
config GPIO_OCTEON
tristate "Cavium OCTEON GPIO"
depends on CAVIUM_OCTEON_SOC
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 010587025fc8..106146f383f3 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -111,6 +111,7 @@ obj-$(CONFIG_GPIO_MT7621) += gpio-mt7621.o
obj-$(CONFIG_GPIO_MVEBU) += gpio-mvebu.o
obj-$(CONFIG_GPIO_MXC) += gpio-mxc.o
obj-$(CONFIG_GPIO_MXS) += gpio-mxs.o
+obj-$(CONFIG_GPIO_NPCM_SGPIO) += gpio-npcm-sgpio.o
obj-$(CONFIG_GPIO_OCTEON) += gpio-octeon.o
obj-$(CONFIG_GPIO_OMAP) += gpio-omap.o
obj-$(CONFIG_GPIO_PALMAS) += gpio-palmas.o
diff --git a/drivers/gpio/gpio-npcm-sgpio.c b/drivers/gpio/gpio-npcm-sgpio.c
new file mode 100644
index 000000000000..9c3896995f8f
--- /dev/null
+++ b/drivers/gpio/gpio-npcm-sgpio.c
@@ -0,0 +1,639 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Nuvoton NPCM Serial GPIO Driver
+ *
+ * Copyright (C) 2021 Nuvoton Technologies
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/gpio/driver.h>
+#include <linux/hashtable.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+
+#define MAX_NR_HW_SGPIO 64
+
+#define NPCM_IOXCFG1 0x2A
+#define NPCM_IOXCFG1_SFT_CLK GENMASK(3, 0)
+#define NPCM_IOXCFG1_SCLK_POL BIT(4)
+#define NPCM_IOXCFG1_LDSH_POL BIT(5)
+
+#define NPCM_IOXCTS 0x28
+#define NPCM_IOXCTS_IOXIF_EN BIT(7)
+#define NPCM_IOXCTS_RD_MODE GENMASK(2, 1)
+#define NPCM_IOXCTS_RD_MODE_PERIODIC BIT(2)
+#define NPCM_IOXCTS_RD_MODE_CONTINUOUS GENMASK(2, 1)
+
+#define NPCM_IOXCFG2 0x2B
+#define NPCM_IXOEVCFG_MASK 0x3
+#define NPCM_IXOEVCFG_BOTH 0x3
+#define NPCM_IXOEVCFG_FALLING 0x2
+#define NPCM_IXOEVCFG_RISING 0x1
+
+#define GPIO_BANK(x) ((x) / 8)
+#define GPIO_BIT(x) ((x) % 8)
+
+/*
+ * Slect the freqency of shift clock.
Selectª.
2. frequency
+ * The shift clock is a division of the APB clock.
+ */
+struct npcm_clk_cfg {
+ const int *SFT_CLK;
+ const u8 *CLK_SEL;
+ const u8 cfg_opt;
+};
+
+struct npcm_sgpio {
+ struct gpio_chip chip;
+ struct clk *pclk;
+ struct irq_chip intc;
+ spinlock_t lock; /*protect event config*/
+ void __iomem *base;
+ int irq;
+ u8 nin_sgpio;
+ u8 nout_sgpio;
+ u8 in_port;
+ u8 out_port;
+ u8 int_type[MAX_NR_HW_SGPIO];
+};
+
+struct npcm_sgpio_bank {
+ u8 rdata_reg;
+ u8 wdata_reg;
+ u8 event_config;
+ u8 event_status;
+};
+
+enum npcm_sgpio_reg {
+ READ_DATA,
+ WRITE_DATA,
+ EVENT_CFG,
+ EVENT_STS,
+};
+
+static const struct npcm_sgpio_bank npcm_sgpio_banks[] = {
+ {
+ .wdata_reg = 0x00,
+ .rdata_reg = 0x08,
+ .event_config = 0x10,
+ .event_status = 0x20,
+ },
+ {
+ .wdata_reg = 0x01,
+ .rdata_reg = 0x09,
+ .event_config = 0x12,
+ .event_status = 0x21,
+ },
+ {
+ .wdata_reg = 0x02,
+ .rdata_reg = 0x0a,
+ .event_config = 0x14,
+ .event_status = 0x22,
+ },
+ {
+ .wdata_reg = 0x03,
+ .rdata_reg = 0x0b,
+ .event_config = 0x16,
+ .event_status = 0x23,
+ },
+ {
+ .wdata_reg = 0x04,
+ .rdata_reg = 0x0c,
+ .event_config = 0x18,
+ .event_status = 0x24,
+ },
+ {
+ .wdata_reg = 0x05,
+ .rdata_reg = 0x0d,
+ .event_config = 0x1a,
+ .event_status = 0x25,
+ },
+ {
+ .wdata_reg = 0x06,
+ .rdata_reg = 0x0e,
+ .event_config = 0x1c,
+ .event_status = 0x26,
+ },
+ {
+ .wdata_reg = 0x07,
+ .rdata_reg = 0x0f,
+ .event_config = 0x1e,
+ .event_status = 0x27,
+ },
+
+};
+
+static void __iomem *bank_reg(struct npcm_sgpio *gpio,
+ const struct npcm_sgpio_bank *bank,
+ const enum npcm_sgpio_reg reg)
+{
+ switch (reg) {
+ case READ_DATA:
+ return gpio->base + bank->rdata_reg;
+ case WRITE_DATA:
+ return gpio->base + bank->wdata_reg;
+ case EVENT_CFG:
+ return gpio->base + bank->event_config;
+ case EVENT_STS:
+ return gpio->base + bank->event_status;
+ default:
+ /* acturally if code runs to here, it's an error case */
+ WARN(1, "NPCM SGPIO REG SET failed!!\n");
+ }
+}
+
+static const struct npcm_sgpio_bank *to_bank(unsigned int offset)
+{
+ unsigned int bank = GPIO_BANK(offset);
+
+ return &npcm_sgpio_banks[bank];
+}
+
+static void irqd_to_npcm_sgpio_data(struct irq_data *d,
+ struct npcm_sgpio **gpio,
+ const struct npcm_sgpio_bank **bank,
+ u8 *bit, int *offset)
+{
+ struct npcm_sgpio *internal;
+
+ *offset = irqd_to_hwirq(d);
+ internal = irq_data_get_irq_chip_data(d);
+ WARN_ON(!internal);
+
+ *gpio = internal;
+ *offset -= internal->nout_sgpio;
+ *bank = to_bank(*offset);
+ *bit = GPIO_BIT(*offset);
+}
+
+static int npcm_sgpio_init_valid_mask(struct gpio_chip *gc,
+ unsigned long *valid_mask, unsigned int ngpios)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ u8 in_port, out_port, set_port;
+
+ in_port = gpio->nin_sgpio / 8;
+ if (gpio->nin_sgpio % 8 > 0)
+ in_port += 1;
+
+ out_port = gpio->nout_sgpio / 8;
+ if (gpio->nout_sgpio % 8 > 0)
+ out_port += 1;
+
+ gpio->in_port = in_port;
+ gpio->out_port = out_port;
+ set_port = ((out_port & 0xf) << 4) | (in_port & 0xf);
+ iowrite8(set_port, gpio->base + NPCM_IOXCFG2);
+
+ return 0;
+}
+
+static int npcm_sgpio_dir_in(struct gpio_chip *gc, unsigned int offset)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+
+ if (offset < gpio->nout_sgpio)
+ return -EINVAL;
+
+ return 0;
If you like, you could write:
return offset < gpio->nout_sgpio ? -EINVAL : 0;
+}
+
+static int npcm_sgpio_dir_out(struct gpio_chip *gc, unsigned int offset, int val)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+
+ if (offset < gpio->nout_sgpio) {
+ gc->set(gc, offset, val);
+ return 0;
+ }
+ return -EINVAL;
Above is a blank line before the `return` statement.
+}
+
+static int npcm_sgpio_get_direction(struct gpio_chip *gc, unsigned int offset)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+
+ if (offset < gpio->nout_sgpio)
+ return 0;
+ return 1;
+}
+
+static void npcm_sgpio_set(struct gpio_chip *gc, unsigned int offset, int val)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ const struct npcm_sgpio_bank *bank = to_bank(offset);
+ void __iomem *addr;
+ u8 reg = 0;
+
+ addr = bank_reg(gpio, bank, WRITE_DATA);
+ reg = ioread8(addr);
+
+ if (val) {
+ reg |= (val << GPIO_BIT(offset));
+ iowrite8(reg, addr);
+ } else {
+ reg &= ~(1 << GPIO_BIT(offset));
+ iowrite8(reg, addr);
+ }
+}
+
+static int npcm_sgpio_get(struct gpio_chip *gc, unsigned int offset)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ const struct npcm_sgpio_bank *bank;
+ void __iomem *addr;
+ u8 dir, reg;
+
+ dir = npcm_sgpio_get_direction(gc, offset);
Is the variable `dir` needed? If yes, please use `int` as that is the
type of the return value, and is more performant than fixed width type [1].
+ if (dir == 0) {
+ bank = to_bank(offset);
+
+ addr = bank_reg(gpio, bank, WRITE_DATA);
+ reg = ioread8(addr);
+ reg = (reg >> GPIO_BIT(offset)) & 0x01;
+ } else {
+ offset -= gpio->nout_sgpio;
+ bank = to_bank(offset);
+
+ addr = bank_reg(gpio, bank, READ_DATA);
+ reg = ioread8(addr);
+ reg = (reg >> GPIO_BIT(offset)) & 0x01;
+ }
+
+ return reg;
+}
+
+static void npcm_sgpio_setup_enable(struct npcm_sgpio *gpio, bool enable)
+{
+ u8 reg = 0;
+
+ reg = ioread8(gpio->base + NPCM_IOXCTS);
+ reg = reg & ~NPCM_IOXCTS_RD_MODE;
+ reg = reg | NPCM_IOXCTS_RD_MODE_PERIODIC;
+
+ if (enable) {
+ reg |= NPCM_IOXCTS_IOXIF_EN;
+ iowrite8(reg, gpio->base + NPCM_IOXCTS);
+ } else {
+ reg &= ~NPCM_IOXCTS_IOXIF_EN;
+ iowrite8(reg, gpio->base + NPCM_IOXCTS);
+ }
+}
+
+static int npcm_sgpio_setup_clk(struct npcm_sgpio *gpio,
+ const struct npcm_clk_cfg *clk_cfg, u32 sgpio_freq)
+{
+ unsigned long apb_freq;
+ u32 sgpio_clk_div;
+ u8 tmp;
+ int i;
+
+ apb_freq = clk_get_rate(gpio->pclk);
+ sgpio_clk_div = (apb_freq / sgpio_freq);
+ if ((apb_freq % sgpio_freq) != 0)
+ sgpio_clk_div += 1;
+
+ tmp = ioread8(gpio->base + NPCM_IOXCFG1) & ~NPCM_IOXCFG1_SFT_CLK;
+
+ for (i = 0; i < clk_cfg->cfg_opt; i++) {
+ if (sgpio_clk_div >= clk_cfg->SFT_CLK[i]) {
+ iowrite8(clk_cfg->CLK_SEL[i] | tmp, gpio->base + NPCM_IOXCFG1);
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+static void npcm_sgpio_irq_init_valid_mask(struct gpio_chip *gc,
+ unsigned long *valid_mask, unsigned int ngpios)
+{
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ int n = gpio->nin_sgpio;
+
+ /* input GPIOs in the high range */
+ bitmap_set(valid_mask, gpio->nout_sgpio, n);
+ bitmap_clear(valid_mask, 0, gpio->nout_sgpio);
+}
+
+static void npcm_sgpio_irq_set_mask(struct irq_data *d, bool set)
+{
+ const struct npcm_sgpio_bank *bank;
+ struct npcm_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *addr;
+ int offset;
+ u16 reg, type;
+ u8 bit;
+
+ irqd_to_npcm_sgpio_data(d, &gpio, &bank, &bit, &offset);
+ addr = bank_reg(gpio, bank, EVENT_CFG);
+
+ spin_lock_irqsave(&gpio->lock, flags);
+
+ npcm_sgpio_setup_enable(gpio, false);
+
+ reg = ioread16(addr);
+ if (set) {
+ reg &= ~(NPCM_IXOEVCFG_MASK << (bit * 2));
+ } else {
+ type = gpio->int_type[offset];
+ reg |= (type << (bit * 2));
+ }
+
+ iowrite16(reg, addr);
+
+ npcm_sgpio_setup_enable(gpio, true);
+
+ addr = bank_reg(gpio, bank, EVENT_STS);
+ reg = ioread8(addr);
+ reg |= BIT(bit);
+ iowrite8(reg, addr);
+
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void npcm_sgpio_irq_ack(struct irq_data *d)
+{
+ const struct npcm_sgpio_bank *bank;
+ struct npcm_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *status_addr;
+ int offset;
+ u8 bit;
+
+ irqd_to_npcm_sgpio_data(d, &gpio, &bank, &bit, &offset);
+ status_addr = bank_reg(gpio, bank, EVENT_STS);
+ spin_lock_irqsave(&gpio->lock, flags);
+ iowrite8(BIT(bit), status_addr);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+}
+
+static void npcm_sgpio_irq_mask(struct irq_data *d)
+{
+ npcm_sgpio_irq_set_mask(d, true);
+}
+
+static void npcm_sgpio_irq_unmask(struct irq_data *d)
+{
+ npcm_sgpio_irq_set_mask(d, false);
+}
+
+static int npcm_sgpio_set_type(struct irq_data *d, unsigned int type)
+{
+ const struct npcm_sgpio_bank *bank;
+ irq_flow_handler_t handler;
+ struct npcm_sgpio *gpio;
+ unsigned long flags;
+ void __iomem *addr;
+ int offset;
+ u16 reg, val;
+ u8 bit;
+
+ irqd_to_npcm_sgpio_data(d, &gpio, &bank, &bit, &offset);
+
+ switch (type & IRQ_TYPE_SENSE_MASK) {
+ case IRQ_TYPE_EDGE_BOTH:
+ val = NPCM_IXOEVCFG_BOTH;
+ handler = handle_edge_irq;
+ break;
+ case IRQ_TYPE_EDGE_RISING:
+ val = NPCM_IXOEVCFG_RISING;
+ handler = handle_edge_irq;
+ break;
+ case IRQ_TYPE_EDGE_FALLING:
+ val = NPCM_IXOEVCFG_FALLING;
+ handler = handle_edge_irq;
+ break;
+ case IRQ_TYPE_LEVEL_HIGH:
+ val = NPCM_IXOEVCFG_RISING;
+ handler = handle_level_irq;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ val = NPCM_IXOEVCFG_FALLING;
+ handler = handle_level_irq;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ gpio->int_type[offset] = val;
+
+ spin_lock_irqsave(&gpio->lock, flags);
+ npcm_sgpio_setup_enable(gpio, false);
+ addr = bank_reg(gpio, bank, EVENT_CFG);
+ reg = ioread16(addr);
+
+ reg |= (val << (bit * 2));
+
+ iowrite16(reg, addr);
+ npcm_sgpio_setup_enable(gpio, true);
+ spin_unlock_irqrestore(&gpio->lock, flags);
+
+ irq_set_handler_locked(d, handler);
+
+ return 0;
+}
+
+static void npcm_sgpio_irq_handler(struct irq_desc *desc)
+{
+ struct gpio_chip *gc = irq_desc_get_handler_data(desc);
+ struct irq_chip *ic = irq_desc_get_chip(desc);
+ struct npcm_sgpio *gpio = gpiochip_get_data(gc);
+ unsigned int i, j, girq;
+ unsigned long reg;
+
+ chained_irq_enter(ic, desc);
+
+ for (i = 0; i < ARRAY_SIZE(npcm_sgpio_banks); i++) {
+ const struct npcm_sgpio_bank *bank = &npcm_sgpio_banks[i];
+
+ reg = ioread8(bank_reg(gpio, bank, EVENT_STS));
+ for_each_set_bit(j, ®, 8) {
+ girq = irq_find_mapping(gc->irq.domain, i * 8 + gpio->nout_sgpio + j);
+ generic_handle_irq(girq);
+ }
+ }
+
+ chained_irq_exit(ic, desc);
+}
+
+static int npcm_sgpio_setup_irqs(struct npcm_sgpio *gpio,
+ struct platform_device *pdev)
+{
+ int rc, i;
+ struct gpio_irq_chip *irq;
+
+ rc = platform_get_irq(pdev, 0);
+ if (rc < 0)
+ return rc;
+
+ gpio->irq = rc;
+
+ npcm_sgpio_setup_enable(gpio, false);
+
+ /* Disable IRQ and clear Interrupt status registers for all SGPIO Pins. */
+ for (i = 0; i < ARRAY_SIZE(npcm_sgpio_banks); i++) {
+ const struct npcm_sgpio_bank *bank = &npcm_sgpio_banks[i];
+
+ iowrite16(0x0000, bank_reg(gpio, bank, EVENT_CFG));
+ iowrite8(0xff, bank_reg(gpio, bank, EVENT_STS));
+ }
+
+ gpio->intc.name = dev_name(&pdev->dev);
+ gpio->intc.irq_ack = npcm_sgpio_irq_ack;
+ gpio->intc.irq_mask = npcm_sgpio_irq_mask;
+ gpio->intc.irq_unmask = npcm_sgpio_irq_unmask;
+ gpio->intc.irq_set_type = npcm_sgpio_set_type;
+
+ irq = &gpio->chip.irq;
+ irq->chip = &gpio->intc;
+ irq->init_valid_mask = npcm_sgpio_irq_init_valid_mask;
+ irq->handler = handle_bad_irq;
+ irq->default_type = IRQ_TYPE_NONE;
+ irq->parent_handler = npcm_sgpio_irq_handler;
+ irq->parent_handler_data = gpio;
+ irq->parents = &gpio->irq;
+ irq->num_parents = 1;
+
+ return 0;
+}
+
+static const int npcm750_SFT_CLK[] = {
+ 1024, 32, 8, 4, 3, 2,
+};
+
+static const u8 npcm750_CLK_SEL[] = {
+ 0x00, 0x05, 0x07, 0x0C, 0x0D, 0x0E,
+};
+
+static const int npcm845_SFT_CLK[] = {
+ 1024, 32, 16, 8, 4,
+};
+
+static const u8 npcm845_CLK_SEL[] = {
+ 0x00, 0x05, 0x06, 0x07, 0x0C,
+};
+
+static const struct npcm_clk_cfg npcm750_sgpio_pdata = {
+ .SFT_CLK = npcm750_SFT_CLK,
+ .CLK_SEL = npcm750_CLK_SEL,
+ .cfg_opt = 6,
+};
+
+static const struct npcm_clk_cfg npcm845_sgpio_pdata = {
You do not mention NPCM845 in the commit message.
+ .SFT_CLK = npcm845_SFT_CLK,
+ .CLK_SEL = npcm845_CLK_SEL,
+ .cfg_opt = 5,
+};
+
+static const struct of_device_id npcm_sgpio_of_table[] = {
+ { .compatible = "nuvoton,npcm750-sgpio", .data = &npcm750_sgpio_pdata, },
+ { .compatible = "nuvoton,npcm845-sgpio", .data = &npcm845_sgpio_pdata, },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, npcm_sgpio_of_table);
+
+static int npcm_sgpio_probe(struct platform_device *pdev)
+{
+ struct npcm_sgpio *gpio;
+ const struct npcm_clk_cfg *clk_cfg;
+ int rc;
+ u32 nin_gpios, nout_gpios, sgpio_freq;
+
+ gpio = devm_kzalloc(&pdev->dev, sizeof(*gpio), GFP_KERNEL);
+ if (!gpio)
+ return -ENOMEM;
+
+ gpio->base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(gpio->base))
+ return PTR_ERR(gpio->base);
+
+ clk_cfg = device_get_match_data(&pdev->dev);
+ if (!clk_cfg)
+ return -EINVAL;
+
+ rc = device_property_read_u32(&pdev->dev, "nin_gpios", &nin_gpios);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "Could not read ngpios property\n");
Mention nin_gpios?
+ return -EINVAL;
+ }
+ rc = device_property_read_u32(&pdev->dev, "nout_gpios", &nout_gpios);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "Could not read ngpios property\n");
+ return -EINVAL;
+ }
+
+ gpio->nin_sgpio = nin_gpios;
+ gpio->nout_sgpio = nout_gpios;
+ if (gpio->nin_sgpio > MAX_NR_HW_SGPIO || gpio->nout_sgpio > MAX_NR_HW_SGPIO) {
+ dev_err(&pdev->dev, "Number of GPIOs exceeds the maximum of %d: input: %d output: %d\n",
+ MAX_NR_HW_SGPIO, nin_gpios, nout_gpios);
+ return -EINVAL;
+ }
+
+ rc = device_property_read_u32(&pdev->dev, "bus-frequency", &sgpio_freq);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "Could not read bus-frequency property\n");
+ return -EINVAL;
+ }
+
+ gpio->pclk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(gpio->pclk)) {
+ dev_err(&pdev->dev, "devm_clk_get failed\n");
For a user, reading such an error message, I’d prefer a more elaborate
message, for example, what won’t work, and that the serial GPIO driver
initialization is aborted.
+ return PTR_ERR(gpio->pclk);
+ }
+
+ rc = npcm_sgpio_setup_clk(gpio, clk_cfg, sgpio_freq);
+ if (rc < 0) {
+ dev_err(&pdev->dev, "Failed to setup clock\n");
+ return -EINVAL;
+ }
+ spin_lock_init(&gpio->lock);
+ gpio->chip.parent = &pdev->dev;
+ gpio->chip.ngpio = gpio->nin_sgpio + gpio->nout_sgpio;
+ gpio->chip.init_valid_mask = npcm_sgpio_init_valid_mask;
+ gpio->chip.direction_input = npcm_sgpio_dir_in;
+ gpio->chip.direction_output = npcm_sgpio_dir_out;
+ gpio->chip.get_direction = npcm_sgpio_get_direction;
+ gpio->chip.request = NULL;
+ gpio->chip.free = NULL;
+ gpio->chip.get = npcm_sgpio_get;
+ gpio->chip.set = npcm_sgpio_set;
+ gpio->chip.set_config = NULL;
+ gpio->chip.label = dev_name(&pdev->dev);
+ gpio->chip.base = -1;
+
+ rc = npcm_sgpio_setup_irqs(gpio, pdev);
+ if (rc < 0)
+ return rc;
+
+ rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
+ if (rc < 0)
+ return rc;
+
+ npcm_sgpio_setup_enable(gpio, true);
+ return 0;
+}
+
+static struct platform_driver npcm_sgpio_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = npcm_sgpio_of_table,
+ },
+ .probe = npcm_sgpio_probe,
+};
+
+module_platform_driver(npcm_sgpio_driver);
+
+MODULE_AUTHOR("Jim Liu <jjliu0@xxxxxxxxxxx>");
+MODULE_AUTHOR("Joseph Liu <kwliu@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("Nuvoton NPCM Serial GPIO Driver");
+MODULE_LICENSE("GPL v2");
Kind regards,
Paul
[1]: https://notabs.org/coding/smallIntsBigPenalty.htm
