diff options
Diffstat (limited to 'drivers/gpu/drm/ast/ast_i2c.c')
| -rw-r--r-- | drivers/gpu/drm/ast/ast_i2c.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/drivers/gpu/drm/ast/ast_i2c.c b/drivers/gpu/drm/ast/ast_i2c.c new file mode 100644 index 000000000000..93e91c36d649 --- /dev/null +++ b/drivers/gpu/drm/ast/ast_i2c.c @@ -0,0 +1,152 @@ +// SPDX-License-Identifier: MIT +/* + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + */ + +#include <drm/drm_managed.h> +#include <drm/drm_print.h> + +#include "ast_drv.h" + +static void ast_i2c_setsda(void *i2c_priv, int data) +{ + struct ast_i2c_chan *i2c = i2c_priv; + struct ast_private *ast = to_ast_private(i2c->dev); + int i; + u8 ujcrb7, jtemp; + + for (i = 0; i < 0x10000; i++) { + ujcrb7 = ((data & 0x01) ? 0 : 1) << 2; + ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf1, ujcrb7); + jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x04); + if (ujcrb7 == jtemp) + break; + } +} + +static void ast_i2c_setscl(void *i2c_priv, int clock) +{ + struct ast_i2c_chan *i2c = i2c_priv; + struct ast_private *ast = to_ast_private(i2c->dev); + int i; + u8 ujcrb7, jtemp; + + for (i = 0; i < 0x10000; i++) { + ujcrb7 = ((clock & 0x01) ? 0 : 1); + ast_set_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0xf4, ujcrb7); + jtemp = ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x01); + if (ujcrb7 == jtemp) + break; + } +} + +static int ast_i2c_getsda(void *i2c_priv) +{ + struct ast_i2c_chan *i2c = i2c_priv; + struct ast_private *ast = to_ast_private(i2c->dev); + uint32_t val, val2, count, pass; + + count = 0; + pass = 0; + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01; + do { + val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01; + if (val == val2) { + pass++; + } else { + pass = 0; + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x20) >> 5) & 0x01; + } + } while ((pass < 5) && (count++ < 0x10000)); + + return val & 1 ? 1 : 0; +} + +static int ast_i2c_getscl(void *i2c_priv) +{ + struct ast_i2c_chan *i2c = i2c_priv; + struct ast_private *ast = to_ast_private(i2c->dev); + uint32_t val, val2, count, pass; + + count = 0; + pass = 0; + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01; + do { + val2 = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01; + if (val == val2) { + pass++; + } else { + pass = 0; + val = (ast_get_index_reg_mask(ast, AST_IO_CRTC_PORT, 0xb7, 0x10) >> 4) & 0x01; + } + } while ((pass < 5) && (count++ < 0x10000)); + + return val & 1 ? 1 : 0; +} + +static void ast_i2c_release(struct drm_device *dev, void *res) +{ + struct ast_i2c_chan *i2c = res; + + i2c_del_adapter(&i2c->adapter); + kfree(i2c); +} + +struct ast_i2c_chan *ast_i2c_create(struct drm_device *dev) +{ + struct ast_i2c_chan *i2c; + int ret; + + i2c = kzalloc(sizeof(struct ast_i2c_chan), GFP_KERNEL); + if (!i2c) + return NULL; + + i2c->adapter.owner = THIS_MODULE; + i2c->adapter.class = I2C_CLASS_DDC; + i2c->adapter.dev.parent = dev->dev; + i2c->dev = dev; + i2c_set_adapdata(&i2c->adapter, i2c); + snprintf(i2c->adapter.name, sizeof(i2c->adapter.name), + "AST i2c bit bus"); + i2c->adapter.algo_data = &i2c->bit; + + i2c->bit.udelay = 20; + i2c->bit.timeout = 2; + i2c->bit.data = i2c; + i2c->bit.setsda = ast_i2c_setsda; + i2c->bit.setscl = ast_i2c_setscl; + i2c->bit.getsda = ast_i2c_getsda; + i2c->bit.getscl = ast_i2c_getscl; + ret = i2c_bit_add_bus(&i2c->adapter); + if (ret) { + drm_err(dev, "Failed to register bit i2c\n"); + goto out_kfree; + } + + ret = drmm_add_action_or_reset(dev, ast_i2c_release, i2c); + if (ret) + return NULL; + return i2c; + +out_kfree: + kfree(i2c); + return NULL; +} |