| /* SPDX-License-Identifier: GPL-2.0+ */ | |
| /* | |
| * comedi_8254.h | |
| * Generic 8254 timer/counter support | |
| * Copyright (C) 2014 H Hartley Sweeten <hsweeten@visionengravers.com> | |
| * | |
| * COMEDI - Linux Control and Measurement Device Interface | |
| * Copyright (C) 2000 David A. Schleef <ds@schleef.org> | |
| */ | |
| #ifndef _COMEDI_8254_H | |
| #define _COMEDI_8254_H | |
| #include <linux/types.h> | |
| #include <linux/errno.h> | |
| #include <linux/err.h> | |
| struct comedi_device; | |
| struct comedi_insn; | |
| struct comedi_subdevice; | |
| /* | |
| * Common oscillator base values in nanoseconds | |
| */ | |
| #define I8254_OSC_BASE_10MHZ 100 | |
| #define I8254_OSC_BASE_5MHZ 200 | |
| #define I8254_OSC_BASE_4MHZ 250 | |
| #define I8254_OSC_BASE_2MHZ 500 | |
| #define I8254_OSC_BASE_1MHZ 1000 | |
| #define I8254_OSC_BASE_100KHZ 10000 | |
| #define I8254_OSC_BASE_10KHZ 100000 | |
| #define I8254_OSC_BASE_1KHZ 1000000 | |
| /* | |
| * I/O access size used to read/write registers | |
| */ | |
| #define I8254_IO8 1 | |
| #define I8254_IO16 2 | |
| #define I8254_IO32 4 | |
| /* | |
| * Register map for generic 8254 timer (I8254_IO8 with 0 regshift) | |
| */ | |
| #define I8254_COUNTER0_REG 0x00 | |
| #define I8254_COUNTER1_REG 0x01 | |
| #define I8254_COUNTER2_REG 0x02 | |
| #define I8254_CTRL_REG 0x03 | |
| #define I8254_CTRL_SEL_CTR(x) ((x) << 6) | |
| #define I8254_CTRL_READBACK(x) (I8254_CTRL_SEL_CTR(3) | BIT(x)) | |
| #define I8254_CTRL_READBACK_COUNT I8254_CTRL_READBACK(4) | |
| #define I8254_CTRL_READBACK_STATUS I8254_CTRL_READBACK(5) | |
| #define I8254_CTRL_READBACK_SEL_CTR(x) (2 << (x)) | |
| #define I8254_CTRL_RW(x) (((x) & 0x3) << 4) | |
| #define I8254_CTRL_LATCH I8254_CTRL_RW(0) | |
| #define I8254_CTRL_LSB_ONLY I8254_CTRL_RW(1) | |
| #define I8254_CTRL_MSB_ONLY I8254_CTRL_RW(2) | |
| #define I8254_CTRL_LSB_MSB I8254_CTRL_RW(3) | |
| /* counter maps zero to 0x10000 */ | |
| #define I8254_MAX_COUNT 0x10000 | |
| struct comedi_8254; | |
| /** | |
| * typedef comedi_8254_iocb_fn - call-back function type for 8254 register access | |
| * @i8254: pointer to struct comedi_8254 | |
| * @dir: direction (0 = read, 1 = write) | |
| * @reg: register number | |
| * @val: value to write | |
| * | |
| * Return: Register value when reading, 0 when writing. | |
| */ | |
| typedef unsigned int comedi_8254_iocb_fn(struct comedi_8254 *i8254, int dir, | |
| unsigned int reg, unsigned int val); | |
| /** | |
| * struct comedi_8254 - private data used by this module | |
| * @iocb: I/O call-back function for register access | |
| * @context: context for register access (e.g. a base address) | |
| * @iosize: I/O size used to access the registers (b/w/l) | |
| * @regshift: register gap shift | |
| * @osc_base: cascaded oscillator speed in ns | |
| * @divisor: divisor for single counter | |
| * @divisor1: divisor loaded into first cascaded counter | |
| * @divisor2: divisor loaded into second cascaded counter | |
| * #next_div: next divisor for single counter | |
| * @next_div1: next divisor to use for first cascaded counter | |
| * @next_div2: next divisor to use for second cascaded counter | |
| * @clock_src; current clock source for each counter (driver specific) | |
| * @gate_src; current gate source for each counter (driver specific) | |
| * @busy: flags used to indicate that a counter is "busy" | |
| * @insn_config: driver specific (*insn_config) callback | |
| */ | |
| struct comedi_8254 { | |
| comedi_8254_iocb_fn *iocb; | |
| unsigned long context; | |
| unsigned int iosize; | |
| unsigned int regshift; | |
| unsigned int osc_base; | |
| unsigned int divisor; | |
| unsigned int divisor1; | |
| unsigned int divisor2; | |
| unsigned int next_div; | |
| unsigned int next_div1; | |
| unsigned int next_div2; | |
| unsigned int clock_src[3]; | |
| unsigned int gate_src[3]; | |
| bool busy[3]; | |
| int (*insn_config)(struct comedi_device *dev, | |
| struct comedi_subdevice *s, | |
| struct comedi_insn *insn, unsigned int *data); | |
| }; | |
| unsigned int comedi_8254_status(struct comedi_8254 *i8254, | |
| unsigned int counter); | |
| unsigned int comedi_8254_read(struct comedi_8254 *i8254, unsigned int counter); | |
| void comedi_8254_write(struct comedi_8254 *i8254, | |
| unsigned int counter, unsigned int val); | |
| int comedi_8254_set_mode(struct comedi_8254 *i8254, | |
| unsigned int counter, unsigned int mode); | |
| int comedi_8254_load(struct comedi_8254 *i8254, | |
| unsigned int counter, unsigned int val, unsigned int mode); | |
| void comedi_8254_pacer_enable(struct comedi_8254 *i8254, | |
| unsigned int counter1, unsigned int counter2, | |
| bool enable); | |
| void comedi_8254_update_divisors(struct comedi_8254 *i8254); | |
| void comedi_8254_cascade_ns_to_timer(struct comedi_8254 *i8254, | |
| unsigned int *nanosec, unsigned int flags); | |
| void comedi_8254_ns_to_timer(struct comedi_8254 *i8254, | |
| unsigned int *nanosec, unsigned int flags); | |
| void comedi_8254_set_busy(struct comedi_8254 *i8254, | |
| unsigned int counter, bool busy); | |
| void comedi_8254_subdevice_init(struct comedi_subdevice *s, | |
| struct comedi_8254 *i8254); | |
| #ifdef CONFIG_HAS_IOPORT | |
| struct comedi_8254 *comedi_8254_io_alloc(unsigned long iobase, | |
| unsigned int osc_base, | |
| unsigned int iosize, | |
| unsigned int regshift); | |
| #else | |
| static inline struct comedi_8254 *comedi_8254_io_alloc(unsigned long iobase, | |
| unsigned int osc_base, | |
| unsigned int iosize, | |
| unsigned int regshift) | |
| { | |
| return ERR_PTR(-ENXIO); | |
| } | |
| #endif | |
| struct comedi_8254 *comedi_8254_mm_alloc(void __iomem *mmio, | |
| unsigned int osc_base, | |
| unsigned int iosize, | |
| unsigned int regshift); | |
| #endif /* _COMEDI_8254_H */ |