diff options
Diffstat (limited to 'drivers/spmi/spmi-sandbox.c')
-rw-r--r-- | drivers/spmi/spmi-sandbox.c | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/drivers/spmi/spmi-sandbox.c b/drivers/spmi/spmi-sandbox.c new file mode 100644 index 0000000..2f0fea0 --- /dev/null +++ b/drivers/spmi/spmi-sandbox.c @@ -0,0 +1,157 @@ +/* + * Sample SPMI bus driver + * + * It emulates bus with single pm8916-like pmic that has only GPIO reigsters. + * + * (C) Copyright 2015 Mateusz Kulikowski <mateusz.kulikowski@gmail.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <errno.h> +#include <spmi/spmi.h> +#include <asm/gpio.h> +#include <asm/io.h> + +DECLARE_GLOBAL_DATA_PTR; + +#define EMUL_GPIO_PID_START 0xC0 +#define EMUL_GPIO_PID_END 0xC3 + +#define EMUL_GPIO_COUNT 4 + +#define EMUL_GPIO_REG_END 0x46 /* Last valid register */ + +#define EMUL_PERM_R 0x1 +#define EMUL_PERM_W 0x2 +#define EMUL_PERM_RW (EMUL_PERM_R | EMUL_PERM_W) + +struct sandbox_emul_fake_regs { + u8 value; + u8 access_mask; + u8 perms; /* Access permissions */ +}; + +struct sandbox_emul_gpio { + struct sandbox_emul_fake_regs r[EMUL_GPIO_REG_END]; /* Fake registers */ +}; + +struct sandbox_spmi_priv { + struct sandbox_emul_gpio gpios[EMUL_GPIO_COUNT]; +}; + +/* Check if valid register was requested */ +static bool check_address_valid(int usid, int pid, int off) +{ + if (usid != 0) + return false; + if (pid < EMUL_GPIO_PID_START || pid > EMUL_GPIO_PID_END) + return false; + if (off > EMUL_GPIO_REG_END) + return false; + return true; +} + +static int sandbox_spmi_write(struct udevice *dev, int usid, int pid, int off, + uint8_t val) +{ + struct sandbox_spmi_priv *priv = dev_get_priv(dev); + struct sandbox_emul_fake_regs *regs; + + if (!check_address_valid(usid, pid, off)) + return -EIO; + + regs = priv->gpios[pid & 0x3].r; /* Last 3 bits of pid are gpio # */ + + switch (off) { + case 0x40: /* Control */ + val &= regs[off].access_mask; + if (((val & 0x30) == 0x10) || ((val & 0x30) == 0x20)) { + /* out/inout - set status register */ + regs[0x8].value &= ~0x1; + regs[0x8].value |= val & 0x1; + } + break; + default: + if (regs[off].perms & EMUL_PERM_W) + regs[off].value = val & regs[off].access_mask; + } + return 0; +} + +static int sandbox_spmi_read(struct udevice *dev, int usid, int pid, int off) +{ + struct sandbox_spmi_priv *priv = dev_get_priv(dev); + struct sandbox_emul_fake_regs *regs; + + if (!check_address_valid(usid, pid, off)) + return -EIO; + + regs = priv->gpios[pid & 0x3].r; /* Last 3 bits of pid are gpio # */ + + if (regs[0x46].value == 0) /* Block disabled */ + return 0; + + switch (off) { + case 0x8: /* Status */ + if (regs[0x46].value == 0) /* Block disabled */ + return 0; + return regs[off].value; + default: + if (regs[off].perms & EMUL_PERM_R) + return regs[off].value; + else + return 0; + } +} + +static struct dm_spmi_ops sandbox_spmi_ops = { + .read = sandbox_spmi_read, + .write = sandbox_spmi_write, +}; + +static int sandbox_spmi_probe(struct udevice *dev) +{ + struct sandbox_spmi_priv *priv = dev_get_priv(dev); + int i; + + for (i = 0; i < EMUL_GPIO_COUNT; ++i) { + struct sandbox_emul_fake_regs *regs = priv->gpios[i].r; + regs[4].perms = EMUL_PERM_R; + regs[4].value = 0x10; + regs[5].perms = EMUL_PERM_R; + regs[5].value = 0x5; + regs[8].access_mask = 0x81; + regs[8].perms = EMUL_PERM_RW; + regs[0x40].access_mask = 0x7F; + regs[0x40].perms = EMUL_PERM_RW; + regs[0x41].access_mask = 7; + regs[0x41].perms = EMUL_PERM_RW; + regs[0x42].access_mask = 7; + regs[0x42].perms = EMUL_PERM_RW; + regs[0x42].value = 0x4; + regs[0x45].access_mask = 0x3F; + regs[0x45].perms = EMUL_PERM_RW; + regs[0x45].value = 0x1; + regs[0x46].access_mask = 0x80; + regs[0x46].perms = EMUL_PERM_RW; + regs[0x46].value = 0x80; + } + return 0; +} + +static const struct udevice_id sandbox_spmi_ids[] = { + { .compatible = "sandbox,spmi" }, + { } +}; + +U_BOOT_DRIVER(msm_spmi) = { + .name = "sandbox_spmi", + .id = UCLASS_SPMI, + .of_match = sandbox_spmi_ids, + .ops = &sandbox_spmi_ops, + .probe = sandbox_spmi_probe, + .priv_auto_alloc_size = sizeof(struct sandbox_spmi_priv), +}; |