diff options
Diffstat (limited to 'drivers/input')
| -rw-r--r-- | drivers/input/Makefile | 1 | ||||
| -rw-r--r-- | drivers/input/mxc_keyb.c | 592 |
2 files changed, 593 insertions, 0 deletions
diff --git a/drivers/input/Makefile b/drivers/input/Makefile index a8e9be2..8b1b86c 100644 --- a/drivers/input/Makefile +++ b/drivers/input/Makefile @@ -14,3 +14,4 @@ obj-$(CONFIG_PS2MULT) += ps2mult.o ps2ser.o endif obj-y += input.o obj-$(CONFIG_OF_CONTROL) += key_matrix.o +obj-$(CONFIG_MXC_KPD) += mxc_keyb.o diff --git a/drivers/input/mxc_keyb.c b/drivers/input/mxc_keyb.c new file mode 100644 index 0000000..813a073 --- /dev/null +++ b/drivers/input/mxc_keyb.c @@ -0,0 +1,592 @@ +/* + * Copyright (C) 2009-2014 Freescale Semiconductor, Inc. All Rights Reserved. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +/*! + * @file mxc_keyb.c + * + * @brief Driver for the Freescale Semiconductor MXC keypad port. + * + * The keypad driver is designed as a standard Input driver which interacts + * with low level keypad port hardware. Upon opening, the Keypad driver + * initializes the keypad port. When the keypad interrupt happens the driver + * calles keypad polling timer and scans the keypad matrix for key + * press/release. If all key press/release happened it comes out of timer and + * waits for key press interrupt. The scancode for key press and release events + * are passed to Input subsytem. + * + * @ingroup keypad + */ + +#include <asm/io.h> +#include <common.h> +#include <asm/errno.h> +#include <linux/types.h> +#include <asm/imx-common/mxc_key_defs.h> +#include <malloc.h> + +/* + * * Module header file + * */ +#include <mxc_keyb.h> + +/*! + * Comment KPP_DEBUG to disable debug messages + */ + +#undef KPP_DEBUG + +#ifdef KPP_DEBUG +#define KPP_PRINTF(fmt, args...) printf(fmt , ##args) + +static void mxc_kpp_dump_regs() +{ + unsigned short t1, t2, t3; + + t1 = __raw_readw(KPCR); + t2 = __raw_readw(KPSR); + t3 = __raw_readw(KDDR); + /* + KPP_PRINTF("KPCR=0x%04x, KPSR=0x%04x, KDDR=0x%04x\n", + t1, t2, t3); + */ +} +#else +#define KPP_PRINTF(fmt, args...) +#endif + +static u16 mxc_key_mapping[] = CONFIG_MXC_KEYMAPPING; + +/*! + * This structure holds the keypad private data structure. + */ +static struct keypad_priv kpp_dev; + +/*! Indicates if the key pad device is enabled. */ + +/*! This static variable indicates whether a key event is pressed/released. */ +static unsigned short KPress; + +/*! cur_rcmap and prev_rcmap array is used to detect key press and release. */ +static unsigned short *cur_rcmap; /* max 64 bits (8x8 matrix) */ +static unsigned short *prev_rcmap; + +/*! + * Debounce polling period(10ms) in system ticks. + */ +/*static unsigned short KScanRate = (10 * CONFIG_SYS_HZ) / 1000;*/ + +/*! + * These arrays are used to store press and release scancodes. + */ +static short **press_scancode; +static short **release_scancode; + +static const unsigned short *mxckpd_keycodes; +static unsigned short mxckpd_keycodes_size; + +/*! + * This function is called to scan the keypad matrix to find out the key press + * and key release events. Make scancode and break scancode are generated for + * key press and key release events. + * + * The following scanning sequence are done for + * keypad row and column scanning, + * -# Write 1's to KPDR[15:8], setting column data to 1's + * -# Configure columns as totem pole outputs(for quick discharging of keypad + * capacitance) + * -# Configure columns as open-drain + * -# Write a single column to 0, others to 1. + * -# Sample row inputs and save data. Multiple key presses can be detected on + * a single column. + * -# Repeat steps the above steps for remaining columns. + * -# Return all columns to 0 in preparation for standby mode. + * -# Clear KPKD and KPKR status bit(s) by writing to a 1, + * Set the KPKR synchronizer chain by writing "1" to KRSS register, + * Clear the KPKD synchronizer chain by writing "1" to KDSC register + * + * @result Number of key pressed/released. + */ +static int mxc_kpp_scan_matrix(void) +{ + unsigned short reg_val; + int col, row; + short scancode = 0; + int keycnt = 0; /* How many keys are still pressed */ + + /* + * wmb() linux kernel function which guarantees orderings in write + * operations + */ + /* wmb(); */ + + /* save cur keypad matrix to prev */ + memcpy(prev_rcmap, cur_rcmap, kpp_dev.kpp_rows * sizeof(prev_rcmap[0])); + memset(cur_rcmap, 0, kpp_dev.kpp_rows * sizeof(cur_rcmap[0])); + + /*1. Disable both (depress and release) keypad interrupts.*/ + + /* KDIE has been disabled in mxc_kpp_getc before calling scan matrix. + * KRIE is always disabled in this driver. + */ + + for (col = 0; col < kpp_dev.kpp_cols; col++) { /* Col */ + /* 2. Write 1.s to KPDR[15:8] setting column data to 1.s */ + reg_val = __raw_readw(KPDR); + reg_val |= 0xff00; + __raw_writew(reg_val, KPDR); + + /* + * 3. Configure columns as totem pole outputs(for quick + * discharging of keypad capacitance) + */ + reg_val = __raw_readw(KPCR); + reg_val &= 0x00ff; + __raw_writew(reg_val, KPCR); + + udelay(2); + +#ifdef KPP_DEBUG + mxc_kpp_dump_regs(); +#endif + + /* + * 4. Configure columns as open-drain + */ + reg_val = __raw_readw(KPCR); + reg_val |= ((1 << kpp_dev.kpp_cols) - 1) << 8; + __raw_writew(reg_val, KPCR); + + /* + * 5. Write a single column to 0, others to 1. + * 6. Sample row inputs and save data. Multiple key presses + * can be detected on a single column. + * 7. Repeat steps 2 - 6 for remaining columns. + */ + + /* Col bit starts at 8th bit in KPDR */ + reg_val = __raw_readw(KPDR); + reg_val &= ~(1 << (8 + col)); + __raw_writew(reg_val, KPDR); + + /* Delay added to avoid propagating the 0 from column to row + * when scanning. */ + + udelay(5); + +#ifdef KPP_DEBUG + mxc_kpp_dump_regs(); +#endif + + /* Read row input */ + reg_val = __raw_readw(KPDR); + for (row = 0; row < kpp_dev.kpp_rows; row++) { /* sample row */ + if (TEST_BIT(reg_val, row) == 0) { + cur_rcmap[row] = BITSET(cur_rcmap[row], col); + keycnt++; + } + } + } + + /* + * 8. Return all columns to 0 in preparation for standby mode. + * 9. Clear KPKD and KPKR status bit(s) by writing to a .1., + * set the KPKR synchronizer chain by writing "1" to KRSS register, + * clear the KPKD synchronizer chain by writing "1" to KDSC register + */ + reg_val = 0x00; + __raw_writew(reg_val, KPDR); + reg_val = __raw_readw(KPDR); + reg_val = __raw_readw(KPSR); + reg_val |= KBD_STAT_KPKD | KBD_STAT_KPKR | KBD_STAT_KRSS | + KBD_STAT_KDSC; + __raw_writew(reg_val, KPSR); + +#ifdef KPP_DEBUG + mxc_kpp_dump_regs(); +#endif + + /* Check key press status change */ + + /* + * prev_rcmap array will contain the previous status of the keypad + * matrix. cur_rcmap array will contains the present status of the + * keypad matrix. If a bit is set in the array, that (row, col) bit is + * pressed, else it is not pressed. + * + * XORing these two variables will give us the change in bit for + * particular row and column. If a bit is set in XOR output, then that + * (row, col) has a change of status from the previous state. From + * the diff variable the key press and key release of row and column + * are found out. + * + * If the key press is determined then scancode for key pressed + * can be generated using the following statement: + * scancode = ((row * 8) + col); + * + * If the key release is determined then scancode for key release + * can be generated using the following statement: + * scancode = ((row * 8) + col) + MXC_KEYRELEASE; + */ + for (row = 0; row < kpp_dev.kpp_rows; row++) { + unsigned char diff; + + /* + * Calculate the change in the keypad row status + */ + diff = prev_rcmap[row] ^ cur_rcmap[row]; + + for (col = 0; col < kpp_dev.kpp_cols; col++) { + if ((diff >> col) & 0x1) { + /* There is a status change on col */ + if ((prev_rcmap[row] & BITSET(0, col)) == 0) { + /* + * Previous state is 0, so now + * a key is pressed + */ + scancode = + ((row * kpp_dev.kpp_cols) + + col); + KPress = 1; + kpp_dev.iKeyState = KStateUp; + + KPP_PRINTF("Press (%d, %d) scan=%d " + "Kpress=%d\n", + row, col, scancode, KPress); + press_scancode[row][col] = + (short)scancode; + } else { + /* + * Previous state is not 0, so + * now a key is released + */ + scancode = + (row * kpp_dev.kpp_cols) + + col + MXC_KEYRELEASE; + KPress = 0; + kpp_dev.iKeyState = KStateDown; + + KPP_PRINTF + ("Release (%d, %d) scan=%d Kpress=%d\n", + row, col, scancode, KPress); + release_scancode[row][col] = + (short)scancode; + keycnt++; + } + } + } + } + + return keycnt; +} + +static int mxc_kpp_reset(void) +{ + unsigned short reg_val; + int i; + + /* + * Stop scanning and wait for interrupt. + * Enable press interrupt and disable release interrupt. + */ + __raw_writew(0x00FF, KPDR); + reg_val = __raw_readw(KPSR); + reg_val |= (KBD_STAT_KPKR | KBD_STAT_KPKD); + reg_val |= KBD_STAT_KRSS | KBD_STAT_KDSC; + __raw_writew(reg_val, KPSR); + reg_val |= KBD_STAT_KDIE; + reg_val &= ~KBD_STAT_KRIE; + __raw_writew(reg_val, KPSR); + +#ifdef KPP_DEBUG + mxc_kpp_dump_regs(); +#endif + + /* + * No more keys pressed... make sure unwanted key codes are + * not given upstairs + */ + for (i = 0; i < kpp_dev.kpp_rows; i++) { + memset(press_scancode[i], -1, + sizeof(press_scancode[0][0]) * kpp_dev.kpp_cols); + memset(release_scancode[i], -1, + sizeof(release_scancode[0][0]) * + kpp_dev.kpp_cols); + } + + return 0; +} + +int mxc_kpp_getc(struct kpp_key_info **key_info) +{ + int col, row; + int key_cnt; + unsigned short reg_val; + short scancode = 0; + int index = 0; + struct kpp_key_info *keyi; + + reg_val = __raw_readw(KPSR); + + if (reg_val & KBD_STAT_KPKD) { + /* + * Disable key press(KDIE status bit) interrupt + */ + reg_val &= ~KBD_STAT_KDIE; + __raw_writew(reg_val, KPSR); + +#ifdef KPP_DEBUG + mxc_kpp_dump_regs(); +#endif + + key_cnt = mxc_kpp_scan_matrix(); + } else { + return 0; + } + + if (key_cnt <= 0) + return 0; + + *key_info = keyi = + (struct kpp_key_info *)malloc + (sizeof(struct kpp_key_info) * key_cnt); + + /* + * This switch case statement is the + * implementation of state machine of debounc + * logic for key press/release. + * The explaination of state machine is as + * follows: + * + * KStateUp State: + * This is in intial state of the state machine + * this state it checks for any key presses. + * The key press can be checked using the + * variable KPress. If KPress is set, then key + * press is identified and switches the to + * KStateFirstDown state for key press to + * debounce. + * + * KStateFirstDown: + * After debounce delay(10ms), if the KPress is + * still set then pass scancode generated to + * input device and change the state to + * KStateDown, else key press debounce is not + * satisfied so change the state to KStateUp. + * + * KStateDown: + * In this state it checks for any key release. + * If KPress variable is cleared, then key + * release is indicated and so, switch the + * state to KStateFirstUp else to state + * KStateDown. + * + * KStateFirstUp: + * After debounce delay(10ms), if the KPress is + * still reset then pass the key release + * scancode to input device and change + * the state to KStateUp else key release is + * not satisfied so change the state to + * KStateDown. + */ + + for (row = 0; row < kpp_dev.kpp_rows; row++) { + for (col = 0; col < kpp_dev.kpp_cols; col++) { + if ((press_scancode[row][col] != -1)) { + /* Still Down, so add scancode */ + scancode = + press_scancode[row][col]; + + keyi[index].val = mxckpd_keycodes[scancode]; + keyi[index++].evt = KDepress; + + KPP_PRINTF("KStateFirstDown: scan=%d val=%d\n", + scancode, mxckpd_keycodes[scancode]); + if (index >= key_cnt) + goto key_detect; + + kpp_dev.iKeyState = KStateDown; + press_scancode[row][col] = -1; + } + } + } + + for (row = 0; row < kpp_dev.kpp_rows; row++) { + for (col = 0; col < kpp_dev.kpp_cols; col++) { + if ((release_scancode[row][col] != -1)) { + scancode = + release_scancode[row][col]; + scancode = + scancode - MXC_KEYRELEASE; + + keyi[index].val = mxckpd_keycodes[scancode]; + keyi[index++].evt = KRelease; + + KPP_PRINTF("KStateFirstUp: scan=%d val=%d\n", + scancode, mxckpd_keycodes[scancode]); + if (index >= key_cnt) + goto key_detect; + + kpp_dev.iKeyState = KStateUp; + release_scancode[row][col] = -1; + } + } + } + +key_detect: + mxc_kpp_reset(); + return key_cnt; +} + +/*! + * This function is called to free the allocated memory for local arrays + */ +static void mxc_kpp_free_allocated(void) +{ + int i; + + if (press_scancode) { + for (i = 0; i < kpp_dev.kpp_rows; i++) { + if (press_scancode[i]) + free(press_scancode[i]); + } + free(press_scancode); + } + + if (release_scancode) { + for (i = 0; i < kpp_dev.kpp_rows; i++) { + if (release_scancode[i]) + free(release_scancode[i]); + } + free(release_scancode); + } + + if (cur_rcmap) + free(cur_rcmap); + + if (prev_rcmap) + free(prev_rcmap); +} + +/*! + * This function is called during the driver binding process. + * + * @param pdev the device structure used to store device specific + * information that is used by the suspend, resume and remove + * functions. + * + * @return The function returns 0 on successful registration. Otherwise returns + * specific error code. + */ +int mxc_kpp_init(void) +{ + int i; + int retval; + unsigned int reg_val; + + kpp_dev.kpp_cols = CONFIG_MXC_KPD_COLMAX; + kpp_dev.kpp_rows = CONFIG_MXC_KPD_ROWMAX; + + /* clock and IOMUX configuration for keypad */ + setup_mxc_kpd(); + + /* Configure keypad */ + + /* Enable number of rows in keypad (KPCR[7:0]) + * Configure keypad columns as open-drain (KPCR[15:8]) + * + * Configure the rows/cols in KPP + * LSB nibble in KPP is for 8 rows + * MSB nibble in KPP is for 8 cols + */ + reg_val = __raw_readw(KPCR); + reg_val |= (1 << kpp_dev.kpp_rows) - 1; /* LSB */ + reg_val |= ((1 << kpp_dev.kpp_cols) - 1) << 8; /* MSB */ + __raw_writew(reg_val, KPCR); + + /* Write 0's to KPDR[15:8] */ + reg_val = __raw_readw(KPDR); + reg_val &= 0x00ff; + __raw_writew(reg_val, KPDR); + + /* Configure columns as output, + * rows as input (KDDR[15:0]) */ + reg_val = __raw_readw(KDDR); + reg_val |= 0xff00; + reg_val &= 0xff00; + __raw_writew(reg_val, KDDR); + + /* Clear the KPKD Status Flag + * and Synchronizer chain. */ + reg_val = __raw_readw(KPSR); + reg_val &= ~(KBD_STAT_KPKR | KBD_STAT_KPKD); + reg_val |= KBD_STAT_KPKD; + reg_val |= KBD_STAT_KRSS | KBD_STAT_KDSC; + __raw_writew(reg_val, KPSR); + /* Set the KDIE control bit, and clear the KRIE + * control bit (avoid false release events). */ + reg_val |= KBD_STAT_KDIE; + reg_val &= ~KBD_STAT_KRIE; + __raw_writew(reg_val, KPSR); + +#ifdef KPP_DEBUG + mxc_kpp_dump_regs(); +#endif + + mxckpd_keycodes = mxc_key_mapping; + mxckpd_keycodes_size = kpp_dev.kpp_cols * kpp_dev.kpp_rows; + + if ((mxckpd_keycodes == (void *)0) + || (mxckpd_keycodes_size == 0)) { + retval = -ENODEV; + goto err; + } + + /* allocate required memory */ + press_scancode = (short **)malloc(kpp_dev.kpp_rows * sizeof(press_scancode[0])); + release_scancode = (short **)malloc(kpp_dev.kpp_rows * sizeof(release_scancode[0])); + + if (!press_scancode || !release_scancode) { + retval = -ENOMEM; + goto err; + } + + for (i = 0; i < kpp_dev.kpp_rows; i++) { + press_scancode[i] = (short *)malloc(kpp_dev.kpp_cols + * sizeof(press_scancode[0][0])); + release_scancode[i] = + (short *)malloc(kpp_dev.kpp_cols * sizeof(release_scancode[0][0])); + + if (!press_scancode[i] || !release_scancode[i]) { + retval = -ENOMEM; + goto err; + } + } + + cur_rcmap = + (unsigned short *)malloc(kpp_dev.kpp_rows * sizeof(cur_rcmap[0])); + prev_rcmap = + (unsigned short *)malloc(kpp_dev.kpp_rows * sizeof(prev_rcmap[0])); + + if (!cur_rcmap || !prev_rcmap) { + retval = -ENOMEM; + goto err; + } + + for (i = 0; i < kpp_dev.kpp_rows; i++) { + memset(press_scancode[i], -1, + sizeof(press_scancode[0][0]) * kpp_dev.kpp_cols); + memset(release_scancode[i], -1, + sizeof(release_scancode[0][0]) * kpp_dev.kpp_cols); + } + memset(cur_rcmap, 0, kpp_dev.kpp_rows * sizeof(cur_rcmap[0])); + memset(prev_rcmap, 0, kpp_dev.kpp_rows * sizeof(prev_rcmap[0])); + + return 0; + +err: + mxc_kpp_free_allocated(); + return retval; +} |