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-rw-r--r--drivers/char/aspeed/ast_kcs.c446
1 files changed, 446 insertions, 0 deletions
diff --git a/drivers/char/aspeed/ast_kcs.c b/drivers/char/aspeed/ast_kcs.c
new file mode 100644
index 0000000..93c079f
--- /dev/null
+++ b/drivers/char/aspeed/ast_kcs.c
@@ -0,0 +1,446 @@
+/*
+ * ASPEED AST2100/2050/2200/2150/2300 KCS controller driver
+ *
+ * (C) Copyright 2017 Raptor Engineering, LLC
+ * (C) Copyright 2006-2009, American Megatrends Inc.
+ *
+ * Author : Timothy Pearson <tpearson@raptorengineering.com>
+ * Jothiram Selvam <jothirams@ami.com>
+ * Vinay Tandon <vinayt@ami.com>
+ */
+
+// #define DEBUG
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/errno.h>
+#include <linux/ioport.h>
+
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/uaccess.h>
+
+#include <char/kcs/kcs.h>
+#include <mach/ast_kcs.h>
+#include <plat/regs-intr.h>
+
+#define AST_KCS_DRIVER_NAME "ast_kcs"
+
+static void *ast_kcs_virt_base;
+bool kcs_enabled_by_user = 0;
+
+inline uint32_t ast_kcs_read_reg(uint32_t reg)
+{
+ return ioread32(ast_kcs_virt_base + reg);
+}
+
+inline void ast_kcs_write_reg(uint32_t data, uint32_t reg)
+{
+ iowrite32(data, ast_kcs_virt_base + reg);
+}
+
+static void ast_kcs_enable_channel(void)
+{
+ uint32_t reg;
+
+ reg = ast_kcs_read_reg(AST_LPC_HICR0);
+ reg |= (AST_LPC_HICR0_LPC3E | AST_LPC_HICR0_LPC2E | AST_LPC_HICR0_LPC1E);
+ ast_kcs_write_reg(reg, AST_LPC_HICR0);
+
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ reg = ast_kcs_read_reg(AST_LPC_HICRB);
+ reg |= AST_LPC_HICRB0_KCS4E;
+ ast_kcs_write_reg(reg, AST_LPC_HICRB);
+#endif
+}
+
+static void ast_kcs_disable_channel(void)
+{
+ uint32_t reg;
+
+ reg = ast_kcs_read_reg(AST_LPC_HICR0);
+ reg &= ~(AST_LPC_HICR0_LPC3E | AST_LPC_HICR0_LPC2E | AST_LPC_HICR0_LPC1E);
+ ast_kcs_write_reg(reg, AST_LPC_HICR0);
+
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ reg = ast_kcs_read_reg(AST_LPC_HICRB);
+ reg &= ~(AST_LPC_HICRB0_KCS4E );
+ ast_kcs_write_reg(reg, AST_LPC_HICRB);
+#endif
+}
+
+static void ast_kcs_configure_io_port_addr(void)
+{
+ uint32_t reg;
+
+ /* switch the access of LADR12 to LADR1 */
+ reg = ast_kcs_read_reg(AST_LPC_HICR4);
+ reg &= ~AST_LPC_HICR4_LADR12SEL;
+ ast_kcs_write_reg(reg, AST_LPC_HICR4);
+
+ mb();
+
+ /* set I/O port address of channel 1*/
+ ast_kcs_write_reg(AST_KCS_ADR1_HI, AST_LPC_LADR12H);
+ ast_kcs_write_reg(AST_KCS_ADR1_LO, AST_LPC_LADR12L);
+
+ mb();
+
+ /* switch the access of LADR12 to LADR2 */
+ reg = ast_kcs_read_reg(AST_LPC_HICR4);
+ reg |= AST_LPC_HICR4_LADR12SEL;
+ ast_kcs_write_reg(reg, AST_LPC_HICR4);
+
+ mb();
+
+ /* set I/O port address 2 */
+ ast_kcs_write_reg(AST_KCS_ADR2_HI, AST_LPC_LADR12H);
+ ast_kcs_write_reg(AST_KCS_ADR2_LO, AST_LPC_LADR12L);
+
+ mb();
+
+ /* enable KCS in channel 3 */
+ reg = ast_kcs_read_reg(AST_LPC_HICR4);
+ reg |= AST_LPC_HICR4_KCSENBL;
+ ast_kcs_write_reg(reg, AST_LPC_HICR4);
+
+ mb();
+
+ /* set I/O port address of channel 3 */
+ ast_kcs_write_reg(AST_KCS_ADR3_HI, AST_LPC_LADR3H);
+ ast_kcs_write_reg(AST_KCS_ADR3_LO, AST_LPC_LADR3L);
+
+ mb();
+
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ /* enable KCS in channel 4 */
+ reg = ast_kcs_read_reg(AST_LPC_HICRB);
+ reg |= AST_LPC_HICRB0_KCS4E;
+ ast_kcs_write_reg(reg, AST_LPC_HICRB);
+
+ mb();
+
+ /* set I/O port address of channel 4 */
+ ast_kcs_write_reg(AST_KCS_ADR4, AST_LPC_LADR4);
+#endif
+
+}
+
+static unsigned char ast_kcs_num_ch(void)
+{
+ return AST_KCS_CHANNEL_NUM;
+}
+
+static void ast_kcs_enable_interrupt(void)
+{
+ uint32_t reg;
+
+ reg = ast_kcs_read_reg(AST_LPC_HICR2);
+ reg |= (AST_LPC_HICR2_IBFIE1 | AST_LPC_HICR2_IBFIE2 | AST_LPC_HICR2_IBFIE3);
+ ast_kcs_write_reg(reg, AST_LPC_HICR2);
+
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ reg = ast_kcs_read_reg(AST_LPC_HICRB);
+ reg |= (AST_LPC_HICRB0_KCS4INTE);
+ ast_kcs_write_reg(reg, AST_LPC_HICRB);
+#endif
+}
+
+static void ast_kcs_disable_interrupt(void)
+{
+ uint32_t reg;
+
+ reg = ast_kcs_read_reg(AST_LPC_HICR2);
+ reg &= ~(AST_LPC_HICR2_IBFIE1 | AST_LPC_HICR2_IBFIE2 | AST_LPC_HICR2_IBFIE3);
+ ast_kcs_write_reg(reg, AST_LPC_HICR2);
+
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ reg = ast_kcs_read_reg(AST_LPC_HICRB);
+ reg &= ~(AST_LPC_HICRB0_KCS4INTE);
+ ast_kcs_write_reg(reg, AST_LPC_HICRB);
+#endif
+}
+
+static void ast_kcs_read_status(u8 channel, u8 *status)
+{
+ if (channel == 3)
+ {
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ *status = (uint8_t) ast_kcs_read_reg(AST_LPC_STR4);
+#endif
+ }
+ else
+ *status = (uint8_t) ast_kcs_read_reg(AST_LPC_STR_CH(channel));
+}
+
+static void ast_kcs_write_status(u8 channel, u8 status)
+{
+ if (channel == 3)
+ {
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ ast_kcs_write_reg(status, AST_LPC_STR4);
+#endif
+ }
+ else
+ ast_kcs_write_reg(status, AST_LPC_STR_CH(channel));
+
+}
+
+static void ast_kcs_read_command(u8 channel, u8 *command)
+{
+ if (channel == 3)
+ {
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ *command = (uint8_t) ast_kcs_read_reg(AST_LPC_IDR4);
+#endif
+ }
+ else
+ *command = (uint8_t) ast_kcs_read_reg(AST_LPC_IDR_CH(channel));
+}
+
+static void ast_kcs_read_data(u8 channel, u8 *data)
+{
+ if(channel == 3)
+ {
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ *data = (uint8_t) ast_kcs_read_reg(AST_LPC_IDR4);
+#endif
+ }
+ else
+ *data = (uint8_t) ast_kcs_read_reg(AST_LPC_IDR_CH(channel));
+}
+
+static void ast_kcs_write_data(u8 channel, u8 data)
+{
+ if (channel == 3)
+ {
+#if defined(CONFIG_ARCH_AST2300) || defined(CONFIG_ARCH_AST2400)
+ ast_kcs_write_reg(data, AST_LPC_ODR4);
+#endif
+ }
+ else
+ ast_kcs_write_reg(data, AST_LPC_ODR_CH(channel));
+}
+
+void
+ast_kcs_interrupt_enable_user (void)
+{
+ kcs_enabled_by_user = 1;
+ ast_kcs_enable_interrupt();
+}
+
+void
+ast_kcs_interrupt_disable_user (void)
+{
+ kcs_enabled_by_user = 0;
+ ast_kcs_disable_interrupt();
+}
+
+static kcs_driver_operations_t ast_kcs_hw_ops = {
+ .num_kcs_ch = ast_kcs_num_ch,
+ .enable_kcs_interrupt = ast_kcs_enable_interrupt,
+ .disable_kcs_interrupt = ast_kcs_disable_interrupt,
+ .read_kcs_status = ast_kcs_read_status,
+ .write_kcs_status = ast_kcs_write_status,
+ .read_kcs_command = ast_kcs_read_command,
+ .read_kcs_data_in = ast_kcs_read_data,
+ .write_kcs_data_out = ast_kcs_write_data,
+ .kcs_interrupt_enable_user = ast_kcs_interrupt_enable_user,
+ .kcs_interrupt_disable_user = ast_kcs_interrupt_disable_user
+};
+
+static irqreturn_t ast_kcs_irq_handler(int irq, void *dev_id)
+{
+ uint32_t reg;
+ int ch;
+ int ret;
+ uint8_t status;
+ int handled;
+
+ reg = ast_kcs_read_reg(AST_LPC_HICR6);
+
+ if (reg & (AST_LPC_HICR6_SNP0_STR | AST_LPC_HICR6_SNP1_STR)) { /* snoop interrupt is occured */
+ return IRQ_NONE; /* handled by snoop driver */
+ }
+
+ reg = ast_kcs_read_reg(AST_LPC_HICR2);
+
+ if (reg & (AST_LPC_HICR2_LRST | AST_LPC_HICR2_SDWN | AST_LPC_HICR2_ABRT)) { /* LRESET | SDWN | ABRT interrupt is occured */
+ return IRQ_NONE; /* handled by LPC-reset driver */
+ }
+ for (ch = 0; ch < AST_KCS_CHANNEL_NUM; ch ++) {
+ ast_kcs_read_status(ch, &status);
+ if (status & 0x02) { /* Command or Data_In register has been written by system-side software */
+ handled = 1;
+ ret = process_kcs_intr(ch);
+ if ((ret != 0) && (ret != -ENXIO)) {
+ printk(KERN_WARNING "KCS core IRQ handler failed\n");
+ }
+ }
+ /* when the KCS core IRQ handler reads IDR, IDF is cleared automatically */
+ }
+
+ return (handled == 1) ? IRQ_HANDLED : IRQ_NONE;
+}
+
+static void ast_kcs_init_hw(void)
+{
+ uint32_t reg;
+ int ch;
+ u8 ch_num, status;
+
+#ifdef SOC_AST2300
+ reg = ast_kcs_read_reg(AST_LPC_HICR5);
+ reg &= ~(0x00000500); /* clear bit 10 & 8 to disable LPC flash cycle */
+ ast_kcs_write_reg(reg, AST_LPC_HICR5);
+#endif
+
+ ast_kcs_disable_interrupt();
+ ast_kcs_disable_channel();
+
+ ast_kcs_configure_io_port_addr();
+
+ /* clear OBF */
+ for (ch = 0; ch < AST_KCS_CHANNEL_NUM; ch ++) {
+ if(ch == 3)
+ {
+#ifdef SOC_AST2300
+ reg = ast_kcs_read_reg(AST_LPC_STR4);
+ reg &= ~AST_LPC_STR_OBFA;
+ ast_kcs_write_reg(reg, AST_LPC_STR4);
+#endif
+ }
+ else
+ {
+ reg = ast_kcs_read_reg(AST_LPC_STR_CH(ch));
+ reg &= ~AST_LPC_STR_OBFA;
+ ast_kcs_write_reg(reg, AST_LPC_STR_CH(ch));
+ }
+ }
+ for (ch_num = 0; ch_num < AST_KCS_CHANNEL_NUM; ++ch_num)
+ {
+ ast_kcs_read_status (ch_num, &status);
+ status = status | ERROR_STATE;
+ ast_kcs_write_status (ch_num, status);
+ }
+
+ ast_kcs_enable_channel();
+ // ast_kcs_enable_interrupt();
+}
+
+static int ast_kcs_probe(struct platform_device *pdev) {
+ int ret = 0;
+ struct resource *res0;
+
+ dev_dbg(&pdev->dev, "ast_kcs_probe() \n\n\n");
+
+ ret = kcs_init(&ast_kcs_hw_ops, pdev->id, THIS_MODULE);
+ if (ret) {
+ printk(KERN_WARNING "%s: initialization of KCS library failed\n", AST_KCS_DRIVER_NAME);
+ return ret;
+ }
+
+ res0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res0) {
+ dev_err(&pdev->dev, "cannot get IORESOURCE_MEM 0\n");
+ goto err_no_io_res;
+ }
+
+ ast_kcs_virt_base = ioremap(res0->start, resource_size(res0));
+ if (!ast_kcs_virt_base) {
+ printk(KERN_WARNING "%s: ioremap failed\n", AST_KCS_DRIVER_NAME);
+ ret = -ENOMEM;
+ goto err_no_io_res;
+ }
+
+ IRQ_SET_LEVEL_TRIGGER(0, AST_KCS_IRQ);
+ IRQ_SET_HIGH_LEVEL(0, AST_KCS_IRQ);
+
+ ret = request_irq(AST_KCS_IRQ, ast_kcs_irq_handler, IRQF_SHARED, AST_KCS_DRIVER_NAME, ast_kcs_virt_base);
+ if (ret) {
+ printk(KERN_WARNING "%s: request irq failed\n", AST_KCS_DRIVER_NAME);
+ goto out_iomap;
+ }
+
+ ast_kcs_init_hw();
+
+ return 0;
+
+out_iomap:
+ iounmap(ast_kcs_virt_base);
+err_no_io_res:
+ kcs_exit();
+
+ return ret;
+}
+
+static int
+ast_kcs_remove(struct platform_device *pdev)
+{
+ struct resource *res0;
+
+ dev_dbg(&pdev->dev, "ast_kcs_remove()\n");
+
+ res0 = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(res0->start, res0->end - res0->start + 1);
+ iounmap(ast_kcs_virt_base);
+
+ platform_set_drvdata(pdev, NULL);
+ kcs_exit();
+ return 0;
+}
+
+
+#ifdef CONFIG_PM
+static int
+ast_kcs_suspend(struct platform_device *pdev, pm_message_t msg)
+{
+ return 0;
+}
+
+static int
+ast_kcs_resume(struct platform_device *pdev)
+{
+ return 0;
+}
+#else
+#define ast_kcs_suspend NULL
+#define ast_kcs_resume NULL
+#endif
+
+
+static struct platform_driver ast_kcs_driver = {
+ .probe = ast_kcs_probe,
+ .remove = ast_kcs_remove,
+ .suspend = ast_kcs_suspend,
+ .resume = ast_kcs_resume,
+ .driver = {
+ .name = "ast-kcs",
+ .owner = THIS_MODULE,
+ },
+};
+
+static int ast_kcs_module_init(void)
+{
+ platform_driver_register(&ast_kcs_driver);
+
+ return 0;
+}
+
+static void ast_kcs_module_exit(void)
+{
+ free_irq(AST_KCS_IRQ, ast_kcs_virt_base);
+ iounmap(ast_kcs_virt_base);
+ platform_driver_unregister(&ast_kcs_driver);
+ kcs_exit();
+}
+
+module_init(ast_kcs_module_init);
+module_exit(ast_kcs_module_exit);
+
+MODULE_AUTHOR("American Megatrends Inc.");
+MODULE_DESCRIPTION("AST2100/2050/2200/2150/2300 KCS controller driver");
+MODULE_LICENSE("GPL");
+
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