| /* 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> |
| |
| 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 - private data used by this module |
| * @iobase: PIO base address of the registers (in/out) |
| * @mmio: MMIO base address of the registers (read/write) |
| * @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 { |
| unsigned long iobase; |
| void __iomem *mmio; |
| 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); |
| |
| struct comedi_8254 *comedi_8254_init(unsigned long iobase, |
| unsigned int osc_base, |
| unsigned int iosize, |
| unsigned int regshift); |
| struct comedi_8254 *comedi_8254_mm_init(void __iomem *mmio, |
| unsigned int osc_base, |
| unsigned int iosize, |
| unsigned int regshift); |
| |
| #endif /* _COMEDI_8254_H */ |
